arm64: entry: consolidate EL1 exception returns

Following the example of ret_to_user, let's consolidate all the EL1
return paths with a ret_to_kernel helper, rather than each entry point
having its own copy of the return code.

There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-11-mark.rutland@arm.comSigned-off-by: Will Deacon <will@kernel.org>

arch/arm64/kernel/entry.S

@@ -611,30 +611,34 @@ SYM_CODE_START_LOCAL(el1_sync)
 	kernel_entry 1
 	mov	x0, sp
 	bl	el1_sync_handler
-	kernel_exit 1
+	b	ret_to_kernel
 SYM_CODE_END(el1_sync)
 
 SYM_CODE_START_LOCAL(el1_irq)
 	kernel_entry 1
 	mov	x0, sp
 	bl	el1_irq_handler
-	kernel_exit 1
+	b	ret_to_kernel
 SYM_CODE_END(el1_irq)
 
 SYM_CODE_START_LOCAL(el1_fiq)
 	kernel_entry 1
 	mov	x0, sp
 	bl	el1_fiq_handler
-	kernel_exit 1
+	b	ret_to_kernel
 SYM_CODE_END(el1_fiq)
 
 SYM_CODE_START_LOCAL(el1_error)
 	kernel_entry 1
 	mov	x0, sp
 	bl	el1_error_handler
-	kernel_exit 1
+	b	ret_to_kernel
 SYM_CODE_END(el1_error)
 
+SYM_CODE_START_LOCAL(ret_to_kernel)
+	kernel_exit 1
+SYM_CODE_END(ret_to_kernel)
+
 /*
  * EL0 mode handlers.
  */