vdso: Remove superfluous #ifdef __KERNEL__ in vdso/datapage.h

With the move to UAPI headers, such #ifdefs are no longer necessary.

Fixes: 361f8aee9b ("vdso: Define standardized vdso_datapage")
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Huw Davies <huw@codeweavers.com>
Cc: Shijith Thotton <sthotton@marvell.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Link: https://lkml.kernel.org/r/20190624135624.GB29120@arrakis.emea.arm.com

include/vdso/datapage.h

@@ -2,8 +2,6 @@
 #ifndef __VDSO_DATAPAGE_H
 #define __VDSO_DATAPAGE_H
 
-#ifdef __KERNEL__
-
 #ifndef __ASSEMBLY__
 
 #include <linux/bits.h>
@@ -88,6 +86,4 @@ extern struct vdso_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")
 
 #endif /* !__ASSEMBLY__ */
 
-#endif /* __KERNEL__ */
-
 #endif /* __VDSO_DATAPAGE_H */