Revises microkernel server command stack processing to allow the
server to support more than 2 types of commands. The lowest 2 bits
of the command now indicate the command's type:
0 - process specified command packet
1 - give specified event (from ISR or fiber)
2 - give specified semaphore (from ISR or fiber)
3 - reserved for future use
Note: Support for type 2 will be provided in a future commit.
Change-Id: I9f83f92a301fb5df3dd479b5d43b187371e11ad8
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>