lzma: Port size-checking ulzman() version to coreboot

We've had a second version of ulzma() that would check the input and
output buffer sizes in libpayload for a while now. Since it's generally
never a bad idea to double-check for overruns, let's port it to coreboot
and use it where applicable. (This requires a small fix in the four byte
at a time read optimization we only have in coreboot, since it made the
stream counter hit the end a little earlier than the algorithm liked and
could trigger an assertion.)

BRANCH=None
BUG=None
TEST=Booted Oak, Jerry and Falco.

Change-Id: Id566b31dfa896ea1b991badf5a6ad9d075aef987
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/13637
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/lib/rmodule.c

@@ -295,7 +295,7 @@ int rmodule_stage_load(struct rmod_stage_load *rsl)
 		if (map == NULL)
 			return -1;
 
-		fsize = ulzma(map, rmod_loc);
+		fsize = ulzman(map, stage.len, rmod_loc, stage.memlen);
 
 		rdev_munmap(fh, map);