Ensure local debug symbols are aligned on AArch64.

Taken from upstream:
https://code.videolan.org/videolan/dav1d/commit/a6228f47f0eebcdfebb1753a786e3e1654b51ea4

diff --git a/src/arm/64/ipred.S b/src/arm/64/ipred.S
index 41b3c1c..9513212 100644
--- a/src/arm/64/ipred.S
+++ b/src/arm/64/ipred.S
@@ -2244,6 +2244,7 @@ L(ipred_cfl_ac_420_tbl):
         .hword L(ipred_cfl_ac_420_tbl) - L(ipred_cfl_ac_420_w16)
         .hword L(ipred_cfl_ac_420_tbl) - L(ipred_cfl_ac_420_w8)
         .hword L(ipred_cfl_ac_420_tbl) - L(ipred_cfl_ac_420_w4)
+        .hword 0
 
 L(ipred_cfl_ac_420_w16_tbl):
         .hword L(ipred_cfl_ac_420_w16_tbl) - L(ipred_cfl_ac_420_w16_wpad0)
@@ -2432,6 +2433,7 @@ L(ipred_cfl_ac_422_tbl):
         .hword L(ipred_cfl_ac_422_tbl) - L(ipred_cfl_ac_422_w16)
         .hword L(ipred_cfl_ac_422_tbl) - L(ipred_cfl_ac_422_w8)
         .hword L(ipred_cfl_ac_422_tbl) - L(ipred_cfl_ac_422_w4)
+        .hword 0
 
 L(ipred_cfl_ac_422_w16_tbl):
         .hword L(ipred_cfl_ac_422_w16_tbl) - L(ipred_cfl_ac_422_w16_wpad0)