target/arm_adi_v5: extend apcsw command to accept arbitrary bits

target/arm_adi_v5: extend apcsw command to accept arbitrary bits

apcsw command was limited to SPROT bit only.

Now user can manipulate any bit except size and addrinc fields.
Can be used e.g. to set bus signal 'cacheable' on Cortex-M7

Change-Id: Ia1c22b208e46d1653136f6faa5a7aaab036de7aa
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: http://openocd.zylin.com/4431
Tested-by: jenkins
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>