MDEV-35566 Ensure compatibility with ARMv9 by updating .arch directive

The pmem_cvap() function currently uses the '.arch armv8.2-a' directive
for the 'dc cvap' instruction. This will cause build errors below when
compiling for ARMv9 systems. Update the '.arch' directive to 'armv9.4-a'
to ensure compatibility with ARMv9 architectures.

{standard input}: Assembler messages:
{standard input}:169: Error: selected processor does not support `retaa'
{standard input}:286: Error: selected processor does not support `retaa'
make[2]: *** [storage/innobase/CMakeFiles/innobase_embedded.dir/build.make:
1644: storage/innobase/CMakeFiles/innobase_embedded.dir/sync/cache.cc.o]
Error 1

Signed-off-by: Ruiqiang Hao <Ruiqiang.Hao@windriver.com>

Author: cythe

storage/innobase/sync/cache.cc

@@ -82,7 +82,12 @@ static void pmem_cvap(const void* buf, size_t size)
   for (uintptr_t u= uintptr_t(buf) & ~(CPU_LEVEL1_DCACHE_LINESIZE),
          end= uintptr_t(buf) + size;
        u < end; u+= CPU_LEVEL1_DCACHE_LINESIZE)
+#if defined __ARM_ARCH && __ARM_ARCH == 9
+    __asm__ __volatile__(".arch armv9.4-a\n dc cvap, %0" :: "r"(u) : "memory");
+#else
     __asm__ __volatile__(".arch armv8.2-a\n dc cvap, %0" :: "r"(u) : "memory");
+#endif
+
   __asm__ __volatile__("dmb ishst" ::: "memory");
 }