ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION

Rather than #define the options manually in the architecture code, add
Kconfig options for them and select them there instead.  This also allows
us to select the compat IPC version parsing automatically for platforms
using the old compat IPC interface.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/Kconfig

@@ -39,6 +39,7 @@ config ARM
 	select GENERIC_IRQ_PROBE
 	select GENERIC_IRQ_SHOW
 	select GENERIC_IRQ_PROBE
+	select ARCH_WANT_IPC_PARSE_VERSION
 	select HARDIRQS_SW_RESEND
 	select CPU_PM if (SUSPEND || CPU_IDLE)
 	select GENERIC_PCI_IOMAP

arch/arm/include/asm/unistd.h

@@ -446,7 +446,6 @@
 
 #ifdef __KERNEL__
 
-#define __ARCH_WANT_IPC_PARSE_VERSION
 #define __ARCH_WANT_STAT64
 #define __ARCH_WANT_SYS_GETHOSTNAME
 #define __ARCH_WANT_SYS_PAUSE