arm64: armv8_deprecated: fix unused-function error

commit 223d3a0 upstream.

If CONFIG_SWP_EMULATION is not set and
CONFIG_CP15_BARRIER_EMULATION is not set,
aarch64-linux-gnu complained about unused-function :

arch/arm64/kernel/armv8_deprecated.c:67:21: error: ‘aarch32_check_condition’ defined but not used [-Werror=unused-function]
 static unsigned int aarch32_check_condition(u32 opcode, u32 psr)
                     ^~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors

To fix this warning, modify aarch32_check_condition() with __maybe_unused.

Fixes: 0c5f416 ("arm64: armv8_deprecated: move aarch32 helper earlier")
Signed-off-by: Ren Zhijie <[email protected]>
Acked-by: Mark Rutland <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Jinjie Ruan <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: Ren Zhijie

arch/arm64/kernel/armv8_deprecated.c

@@ -64,7 +64,7 @@ struct insn_emulation {
 
 #define	ARM_OPCODE_CONDITION_UNCOND	0xf
 
-static unsigned int aarch32_check_condition(u32 opcode, u32 psr)
+static unsigned int __maybe_unused aarch32_check_condition(u32 opcode, u32 psr)
 {
 	u32 cc_bits  = opcode >> 28;