Make TWRP compile for arm64

-Remove dosfstools for arm64 until we can make it compile
-Fix TW_USE_TOOLBOX flag to work again
-Fix symlinking and handling of sh when using mksh
-Fix legacy properties to find futex_wake function
-Fix libcrecovery to not use bsd_signal anymore
-Fix rules for building with regards to libcrecovery
-Update toolbox_recovery rules to compile tools in lollipop
-Fix a few compile errors specific to arm64

Testers report that TWRP does not boot on Nexus 9 and we fail to
get a shell for adb shell. At least it compiles without errors.

Change-Id: I286be8628defb60cc527b8a548c0bdfcb0ebb574
Add lollipop decrypt support

Kang in cryptfs.c and cryptfs.h from vold.
Use TW_INCLUDE_L_CRYPTO := true to enable.
Ramdisk must contain the normal fstab file in the root in the
usual format of:
fstab.{ro.hardware}
For examble for Nexus 5:
fstab.hammerhead
Or on many Qualcomm devices:
fstab.qcom

Tested against Android 5.0 lollipop on Nexus 7 2012 grouper. Not
sure if or how this will work when we are dealing with a device
with a hardware keystore. Long term we need to add a GUI element
to allow entering a pattern. For now you can decrypt a pattern
unlock by converting the dots to numbers in the following format:
123
456
789

So an upper-case L would translate to 14789 as a password entered
on the keyboard.

Change-Id: I02c29e1f1c2eb29bf002c9fe0fc118357300b5b3
Merge pull request #5 from omnirom/android-5.0

Android 5.0 Updates