patch 9.1.1396: 'errorformat' is a global option

Problem:  The 'grepformat' option is global option, but it would be
          useful to have it buffer-local, similar to 'errorformat' and
          other quickfix related options (Dani Dickstein)
Solution: Add the necessary code to support global-local 'grepformat',
          allowing different buffers to parse different grep output
          formats (glepnir)

fixes: #17316
closes: #17315

Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/option.h b/src/option.h
index e78a7cb..740f6ee 100644
--- a/src/option.h
+++ b/src/option.h
@@ -1157,6 +1157,7 @@
     , BV_BT
 #ifdef FEAT_QUICKFIX
     , BV_EFM
+    , BV_GEFM
     , BV_GP
     , BV_MP
 #endif