mds: refactor out fs_name match in MDSAuthCaps

Signed-off-by: Patrick Donnelly <pdonnell@redhat.com>
(cherry picked from commit 247b4fe)

src/mds/MDSAuthCaps.h

@@ -146,6 +146,10 @@ struct MDSCapMatch {
    */
   bool match_path(std::string_view target_path) const;
 
+  bool match_fs(std::string_view target_fs) const {
+    return fs_name == target_fs || fs_name.empty() || fs_name == "*";
+  }
+
   void encode(ceph::buffer::list& bl) const {
     ENCODE_START(1, 1, bl);
     encode(uid, bl);
@@ -261,8 +265,7 @@ class MDSAuthCaps
     }
 
     for (const MDSCapGrant &g : grants) {
-      if (g.match.fs_name == fs_name || g.match.fs_name.empty() ||
-	  g.match.fs_name == "*") {
+      if (g.match.match_fs(fs_name)) {
 	if (mask & MAY_READ && g.spec.allow_read()) {
 	  return true;
 	}