Fix MIPS assembly code to work with newer GCC, where the "=h"
constraint is no longer supported.

--- libmad/fixed.h.orig	2004-02-16 21:02:03.000000000 -0500
+++ libmad/fixed.h	2011-10-29 18:47:21.000000000 -0400
@@ -304,8 +304,8 @@
  * significant bit depends on OPT_ACCURACY via mad_f_scale64().
  */
 #  define MAD_F_MLX(hi, lo, x, y)  \
-    asm ("mult	%2,%3"  \
-	 : "=l" (lo), "=h" (hi)  \
+    asm ("mult	%2,%3\n\tmfhi  %1"  \
+	 : "=l" (lo), "=r" (hi)  \
 	 : "%r" (x), "r" (y))
 
 # if defined(HAVE_MADD_ASM)
a> : <a href='/guix/'>guix</a></td><td class='form'><form method='get'>
<input type='hidden' name='id' value='ef27d1cd1ee701cd61c76b76299d4138476f9e91'/><select name='h' onchange='this.form.submit();'>
<option value='koszko' selected='selected'>koszko</option>
<option value='koszko-scripts'>koszko-scripts</option>
</select> <input type='submit' value='switch'/></form></td></tr>
<tr><td class='sub'>Wojtek's customized Guix</td><td class='sub right'></td></tr></table>
<table class='tabs'><tr><td>
<a href='/guix/about/'>about</a><a href='/guix/'>summary</a><a href='/guix/refs/?id=ef27d1cd1ee701cd61c76b76299d4138476f9e91'>refs</a><a class='active' href='/guix/log/tests/pack.scm'>log</a><a href='/guix/tree/tests/pack.scm?id=ef27d1cd1ee701cd61c76b76299d4138476f9e91'>tree</a><a href='/guix/commit/tests/pack.scm?id=ef27d1cd1ee701cd61c76b76299d4138476f9e91'>commit</a><a href='/guix/diff/tests/pack.scm?id=ef27d1cd1ee701cd61c76b76299d4138476f9e91'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/tests/pack.scm'>
<input type='hidden' name='id' value='ef27d1cd1ee701cd61c76b76299d4138476f9e91'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=ef27d1cd1ee701cd61c76b76299d4138476f9e91'>root</a>/<a href='/guix/log/tests?id=ef27d1cd1ee701cd61c76b76299d4138476f9e91'>tests</a>/<a href='/guix/log/tests/pack.scm?id=ef27d1cd1ee701cd61c76b76299d4138476f9e91'>pack.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/pack.scm?id=ef27d1cd1ee701cd61c76b76299d4138476f9e91&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-07-18 16:56:06 -0400'>2023-07-18</span></td><td><a href='/guix/commit/tests/pack.scm?id=c75022d65f1fa18b8c4839e50f915e8f4d4fe305'>tests: pack: Fix indentation.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2023-07-18 16:56:06 -0400'>2023-07-18</span></td><td><a href='/guix/commit/tests/pack.scm?id=d5f8b50365533f2713596f59519c48019f6b1f19'>pack: Move common build code to (guix build pack).</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2023-03-17 12:14:14 -0400'>2023-03-17</span></td><td><a href='/guix/commit/tests/pack.scm?id=933051281fbed0ae71bd40c24a701faf2a02791c'>Revert "tests: pack: Fix indentation."</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2023-02-27 15:54:09 +0100'>2023-02-27</span></td><td><a href='/guix/commit/tests/pack.scm?id=fee1d08f0dd183ef78bcb9f1534d7b9e7f1df7ac'>pack: Make sure tests can run without a world rebuild.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-02-19 21:13:23 -0500'>2023-02-19</span></td><td><a href='/guix/commit/tests/pack.scm?id=598f4c509bbfec2b983a8ee246cce0a0fe45ec7f'>pack: Add RPM format.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2023-02-19 21:13:23 -0500'>2023-02-19</span></td><td><a href='/guix/commit/tests/pack.scm?id=ac1d530d56c1a259630c8873b2281033878a4acb'>tests: pack: Fix indentation.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2022-10-22 01:46:55 +0200'>2022-10-22</span></td><td><a href='/guix/commit/tests/pack.scm?id=a3619079f95213c4f983e69210ed12b38fd31022'>Remove now unnecessary uses of (guix grafts).</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>