[PATCH] ARM: avoid ARCH_MMAP_RND_BITS for NOMMU

[arnd@arndb.de (Arnd Bergmann)]

ARM kernels with MMU disabled fail to build because of CONFIG_ARCH_MMAP_RND_BITS:

kernel/built-in.o:(.data+0x754): undefined reference to `mmap_rnd_bits'
kernel/built-in.o:(.data+0x76c): undefined reference to `mmap_rnd_bits_min'
kernel/built-in.o:(.data+0x770): undefined reference to `mmap_rnd_bits_max'

This changes the newly added line to only select this allow for
MMU-enabled kernels.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 14570b3fd31a ("arm: mm: support ARCH_MMAP_RND_BITS")
---
Found on yesterday's linux-next with ARM randconfig. The commit that
introduced this is currently in Andrew's tree.

If you don't already have a fix, please either apply this patch on top,
or fold it into the original patch.

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index b64f64d124c4..5a0957e3ea36 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -34,7 +34,7 @@ config ARM
 	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
 	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
 	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
-	select HAVE_ARCH_MMAP_RND_BITS
+	select HAVE_ARCH_MMAP_RND_BITS if MMU
 	select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT)
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_BPF_JIT