tests/checkasm/diracdsp: fix alignment for src and ombc_weight buffers

They are supposed to be 16 byte aligned, not 8.
Should fix crashes in some systems.

Signed-off-by: James Almer <jamrial@gmail.com>

tests/checkasm/diracdsp.c

@@ -50,10 +50,10 @@
 
 static void check_add_obmc(size_t func_index, int xblen)
 {
-    LOCAL_ALIGNED_8(uint8_t, src, [XBLEN_MAX * YBLEN_MAX]);
+    LOCAL_ALIGNED_16(uint8_t, src, [XBLEN_MAX * YBLEN_MAX]);
     LOCAL_ALIGNED_16(uint16_t, _dst0, [XBLEN_MAX * YBLEN_MAX + 4]);
     LOCAL_ALIGNED_16(uint16_t, _dst1, [XBLEN_MAX * YBLEN_MAX + 4]);
-    LOCAL_ALIGNED_8(uint8_t, obmc_weight, [XBLEN_MAX * YBLEN_MAX]);
+    LOCAL_ALIGNED_16(uint8_t, obmc_weight, [XBLEN_MAX * YBLEN_MAX]);
 
     // Ensure that they accept unaligned buffer.
     // Not using LOCAL_ALIGNED_8 because it might make 16 byte aligned buffer.