label_file.h: actually use the results of compat_validate

process_line called compat_validate, but never actually looked at the
return value. When an invalid entry is found, a warning is printed, but
since the upper layers of the code don't see the error, validation
appears to succeed.

Steps to reproduce on Android:

1) Edit system/sepolicy/private/file_contexts and create an entry with
an invalid label.
2) Recompile Android, which executes out/host/linux-x86/bin/checkfc to
check if file_contexts is valid.

Expected: Compile failure.
Actual: Compile succeeds with warnings.

Change-Id: I20fa18c7b11b5ffdd243c3274bedc4518431e1fb
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
1 file changed