patch 8.2.1898: command modifier parsing always uses global cmdmod

Problem:    Command modifier parsing always uses global cmdmod.
Solution:   Pass in cmdmod_T to use.  Rename struct fields consistently.
diff --git a/src/filepath.c b/src/filepath.c
index b692e22..7177275 100644
--- a/src/filepath.c
+++ b/src/filepath.c
@@ -2213,11 +2213,11 @@
     char_u		*fname;
     static char_u	*last_dir = NULL;    // last used directory
     char_u		*tofree = NULL;
-    int			save_browse = cmdmod.browse;
+    int			save_cmod_flags = cmdmod.cmod_flags;
 
     // Must turn off browse to avoid that autocommands will get the
     // flag too!
-    cmdmod.browse = FALSE;
+    cmdmod.cmod_flags &= ~CMOD_BROWSE;
 
     if (title == NULL || *title == NUL)
     {
@@ -2350,7 +2350,7 @@
     }
 
     vim_free(tofree);
-    cmdmod.browse = save_browse;
+    cmdmod.cmod_flags = save_cmod_flags;
 
     return fname;
 }