Disable CPU optimizations not supported by all x86_64 systems.

--- a/cmake/modules/SIMDExt.cmake	2017-03-23 22:22:58.254071694 +0100
+++ b/cmake/modules/SIMDExt.cmake	2017-03-23 22:23:22.446848845 +0100
@@ -5,11 +5,6 @@
 # HAVE_ARM_NEON
 # HAVE_INTEL_SSE
 # HAVE_INTEL_SSE2
-# HAVE_INTEL_SSE3
-# HAVE_INTEL_SSSE3
-# HAVE_INTEL_PCLMUL
-# HAVE_INTEL_SSE4_1
-# HAVE_INTEL_SSE4_2
 #
 # SIMD_COMPILE_FLAGS
 #
@@ -85,26 +80,6 @@
       if(HAVE_INTEL_SSE2)
         set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -msse2")
       endif()
-      CHECK_C_COMPILER_FLAG(-msse3 HAVE_INTEL_SSE3)
-      if(HAVE_INTEL_SSE3)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -msse3")
-      endif()
-      CHECK_C_COMPILER_FLAG(-mssse3 HAVE_INTEL_SSSE3)
-      if(HAVE_INTEL_SSSE3)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -mssse3")
-      endif()
-      CHECK_C_COMPILER_FLAG(-mpclmul HAVE_INTEL_PCLMUL)
-      if(HAVE_INTEL_PCLMUL)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -mpclmul")
-      endif()
-      CHECK_C_COMPILER_FLAG(-msse4.1 HAVE_INTEL_SSE4_1)
-      if(HAVE_INTEL_SSE4_1)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -msse4.1")
-      endif()
-      CHECK_C_COMPILER_FLAG(-msse4.2 HAVE_INTEL_SSE4_2)
-      if(HAVE_INTEL_SSE4_2)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -msse4.2")
-      endif()
     endif(CMAKE_SYSTEM_PROCESSOR MATCHES "amd64|x86_64|AMD64")
   endif(CMAKE_SYSTEM_PROCESSOR MATCHES "i686|amd64|x86_64|AMD64")
 elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "(powerpc|ppc)64le")
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<div class='path'>path: <a href='/guix/log/?id=57be6956ee5daed7c6a8170fc9a664f43bd15d13'>root</a>/<a href='/guix/log/.guix-authorizations?id=57be6956ee5daed7c6a8170fc9a664f43bd15d13'>.guix-authorizations</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/.guix-authorizations?id=57be6956ee5daed7c6a8170fc9a664f43bd15d13&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2024-04-20 13:05:23 -0400'>2024-04-20</span></td><td><a href='/guix/commit/.guix-authorizations?id=43a4215cad8c6da357f895569c0cedf5e854cee0'>Authorize the PGP key of Zheng Junjie (z572).</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2024-04-09 16:17:23 -0400'>2024-04-09</span></td><td><a href='/guix/commit/.guix-authorizations?id=0945e9f17a3fa77cf42665d7487a555adf76b4e8'>.guix-authorizations: Remove Björn Höfling due to inactivity.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2024-04-09 16:10:48 -0400'>2024-04-09</span></td><td><a href='/guix/commit/.guix-authorizations?id=d6a6af892a3c212a088dc518547829994f945625'>.guix-authorizations: Remove Raghav Gururajan due to inactivity.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2024-01-09 23:08:17 -0500'>2024-01-09</span></td><td><a href='/guix/commit/.guix-authorizations?id=e541f9593f8bfc84b6140c2408b393243289fae6'>Authorize Oleg (Sharlatan)'s key.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2023-07-23 22:26:01 -0400'>2023-07-23</span></td><td><a href='/guix/commit/.guix-authorizations?id=4c4222f32a2906b7bcab74fab70ff2c2f152e8eb'>.guix-authorizations: Update lfam's key.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2023-08-13 02:00:00 +0200'>2023-08-13</span></td><td><a href='/guix/commit/.guix-authorizations?id=85dbe6d13f20b884f343032e5d1829cc0ef9000d'>.guix-authorizations: Authorise Hilton Chain.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>