split minijail0 cli parsers into a sep module

This will let us unittest them easily.  The only thing this CL has done
is move all the non-main funcs from minijail0.c to minijail0_cli.c.

Bug: None
Test: `make check` passes
Change-Id: I2be5cf2097d1f8d15270595f5200c872a0a551c4
5 files changed