ANDROID: Revert "mm/mmap: remove __vma_adjust()"

This reverts commit 0503ea8f.

With this commit we cannot boot into Android, zygote gets killed
multiple times until Android gives up and reboots:
    [   62.724034][    T1] init: Service 'zygote' (pid 2991) received signal 7
    [   62.724587][    T1] init: Sending signal 9 to service 'zygote' (pid 2991) process group...
    [   62.725057][    T1] libprocessgroup: Successfully killed process cgroup uid 0 pid 2991 in 0ms
    [   62.730878][    T1] init: critical process 'zygote' exited 4 times before boot completed
    [   62.733498][    T1] init: InitFatalReboot: signal 6
    ...
    [   62.747140][    T1] init:   #00 pc 0000000000159a2c  /system/bin/init (android::init::InitFatalReboot(int)+204)
    [   62.747367][    T1] init:   #01 pc 00000000000e7f30  /system/bin/init (android::init::InitAborter(char const*)+48)
    [   62.747595][    T1] init:   #02 pc 00000000000197a0  /system/lib64/libbase.so (android::base::SetAborter(std::__1::function<void (char const*)>&&)::$_3::__invoke(char const*)+80)
    [   62.748177][    T1] init:   #03 pc 0000000000018ca0  /system/lib64/libbase.so (android::base::LogMessage::~LogMessage()+352)
    [   62.748713][    T1] init:   #04 pc 0000000000101574  /system/bin/init (android::init::Service::Reap(siginfo const&)+2372)
    [   62.749277][    T1] init:   #05 pc 0000000000164d50  /system/bin/init (android::init::ReapOneProcess()+448)
    [   62.749796][    T1] init:   #06 pc 0000000000164b80  /system/bin/init (android::init::ReapAnyOutstandingChildren()+16)
    [   62.750365][    T1] init:   #07 pc 000000000013bc50  /system/bin/init (android::init::Epoll::Wait(std::__1::optional<std::__1::chrono::duration<long long, std::__1::ratio<1l, 1000l> > >)+560)
    [   62.751153][    T1] init:   #08 pc 00000000001283e0  /system/bin/init (android::init::SecondStageMain(int, char**)+8160)
    [   62.751726][    T1] init:   #09 pc 0000000000053a48  /system/lib64/bootstrap/libc.so (__libc_init+104)
    ...
    [   62.752214][    T1] init: Reboot ending, jumping to kernel
    [   62.752432][    T1] debug-reboot: Create reboot monitor timer now
    [   62.755206][    T1] Reboot command: 'zygote-fatal'
    [   62.755282][    T1] Unknown reboot command: 'zygote-fatal'
    ...

Test: build & boot, TH
Bug: 277214742
Change-Id: I4addd51a3b93a0657a44179ee246118ed2daf642
Signed-off-by: André Draszik <draszik@google.com>