x86/kconfig: Clean up 32-bit compat options

Introduce a 'COMPAT_32' helper config value for 'X86_32 || IA32_EMULATION'
and use it.

Also move some selects to this new option, to remove more selects from
the generic X86 section.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/Kconfig

@@ -153,11 +153,9 @@ config X86
 	select HAVE_PERF_USER_STACK_DUMP
 	select HAVE_REGS_AND_STACK_ACCESS_API
 	select HAVE_SYSCALL_TRACEPOINTS
-	select HAVE_UID16			if X86_32 || IA32_EMULATION
 	select HAVE_UNSTABLE_SCHED_CLOCK
 	select HAVE_USER_RETURN_NOTIFIER
 	select IRQ_FORCED_THREADING
-	select OLD_SIGSUSPEND3			if X86_32 || IA32_EMULATION
 	select PERF_EVENTS
 	select RTC_LIB
 	select RTC_MC146818_LIB
@@ -2098,7 +2096,7 @@ config DEBUG_HOTPLUG_CPU0
 config COMPAT_VDSO
 	def_bool n
 	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
-	depends on X86_32 || IA32_EMULATION
+	depends on COMPAT_32
 	---help---
 	  Certain buggy versions of glibc will crash if they are
 	  presented with a 32-bit vDSO that is not mapped at the address
@@ -2728,6 +2726,12 @@ config X86_X32
 	  elf32_x86_64 support enabled to compile a kernel with this
 	  option set.
 
+config COMPAT_32
+	def_bool y
+	depends on IA32_EMULATION || X86_32
+	select HAVE_UID16
+	select OLD_SIGSUSPEND3
+
 config COMPAT
 	def_bool y
 	depends on IA32_EMULATION || X86_X32