target: add "phys" argument to mem2array, array2mem

target: add "phys" argument to mem2array, array2mem

Allow using physical addresses with mem2array and array2mem. In order
to minimize the impact on existing scripts, "phys" is added as an
optional 5th parameter to both commands.

This patch also adds "phys" variants to the memwrite/memread commands
in memory.tcl.

Change-Id: Ia6307f9d861789e7f3ccf1f98961d666bf8d85d6
Signed-off-by: Matthias Welwarsky <matthias.welwarsky@sysgo.com>
Reviewed-on: http://openocd.zylin.com/3387
Tested-by: jenkins
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>