CHROMIUM: ARM64: dragon: update mmap_rnd_bits to max value.

BUG=b:26688196
TEST=smaug boots

Signed-off-by: David Riley <davidriley@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/322712
Reviewed-by: Daniel Cashman <dcashman@google.com>
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
(cherry picked from commit 44c2a9e)
Signed-off-by: David Riley <davidriley@chromium.org>
Change-Id: Ied5270f9e94ed139d6a26790231f6b90484206de
Reviewed-on: https://chrome-internal-review.googlesource.com/245446
Commit-Queue: David Riley <davidriley@google.com>
Tested-by: David Riley <davidriley@google.com>

arch/arm64/configs/dragon_defconfig

@@ -20,6 +20,8 @@ CONFIG_CC_OPTIMIZE_FOR_SIZE=y
 CONFIG_EMBEDDED=y
 # CONFIG_COMPAT_BRK is not set
 CONFIG_PROFILING=y
+CONFIG_ARCH_MMAP_RND_BITS=24
+CONFIG_ARCH_MMAP_RND_COMPAT_BITS=16
 CONFIG_PARTITION_ADVANCED=y
 CONFIG_ARCH_TEGRA=y
 CONFIG_ARCH_TEGRA_132_SOC=y