util/docker: Update makefile target names

- Use dashes instead of underscores for consistency and to match other
coreboot targets
- Fix a couple of places where old target names were referenced
- Remove double 'help' target from .PHONEY target list

Change-Id: I3b464ebf74653a8cc880e982316fd883757ec728
Signed-off-by: Martin Roth <gaumless@gmail.com>
Reviewed-on: https://review.coreboot.org/18000
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
1 file changed