fix ipi_timer race condition
add config: EMU_UART for using TTL serial via micro USB

Much of the original debugging for this driver was done by jonpry
using the 2.6 mapphone kernel.
Fix compile with GCC 4.7
add some rpmsg debugging, remove some boot warnings, (as a side effect audio works)

Conflicts:
	arch/arm/configs/mapphone_spyder_defconfig