Remove redundant optimizations.

Let this be handled by the source makefiles found
at build/core/combo/arch/arm/armv7-a-neon.mk
Remove recovery.rc and unused TARGET_.*_INIT defines.
Enable WEBGL by default.
Enable BOARD_RECOVERY_HANDLES_MOUNT.
Cleanup BoardConfig.

BOARD_PROVIDES_BOOTMODE isn't used and
BOARD_USES_UBOOT only needs to be defined if true.