logcat: add --print flag

(cherry pick from commit c9202777cf0a135be729b1bfdb4c8c57344296e6)

To be used in combination with --regex and --max-count flags
to allow all prints to pass through, but still stop when
max-count is hit.

Bug: 27706081
Change-Id: Idaa9f0b44586a885b9d9f367824b0072c0853227
1 file changed