kselftest/arm64: Fix hwcaps selftest build

The hwcaps selftest currently relies on the assembler being able to
assemble the crc32w instruction but this is not in the base v8.0 so is not
accepted by the standard GCC configurations used by many distributions.
Switch to manually encoding to fix the build.

Fixes: 09d2e95 ("kselftest/arm64: add crc32 feature to hwcap test")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230816-arm64-fix-crc32-build-v1-1-40165c1290f2@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Author: broonie

tools/testing/selftests/arm64/abi/hwcap.c

@@ -48,7 +48,8 @@ static void atomics_sigill(void)
 
 static void crc32_sigill(void)
 {
-	asm volatile("crc32w w0, w0, w1");
+	/* CRC32W W0, W0, W1 */
+	asm volatile(".inst 0x1ac14800" : : : );
 }
 
 static void cssc_sigill(void)