revert(3p/git): Revert merge of git upstream at v2.26.2

This causes cgit to serve error pages, which is undesirable.

This reverts commit 5229c9b232, reversing
changes made to f2b211131f.

third_party/git/gpg-interface.h

@@ -7,14 +7,6 @@ struct strbuf;
 #define GPG_VERIFY_RAW			2
 #define GPG_VERIFY_OMIT_STATUS	4
 
-enum signature_trust_level {
-	TRUST_UNDEFINED,
-	TRUST_NEVER,
-	TRUST_MARGINAL,
-	TRUST_FULLY,
-	TRUST_ULTIMATE,
-};
-
 struct signature_check {
 	char *payload;
 	char *gpg_output;
@@ -24,6 +16,7 @@ struct signature_check {
 	 * possible "result":
 	 * 0 (not checked)
 	 * N (checked but no further result)
+	 * U (untrusted good)
 	 * G (good)
 	 * B (bad)
 	 */
@@ -32,7 +25,6 @@ struct signature_check {
 	char *key;
 	char *fingerprint;
 	char *primary_key_fingerprint;
-	enum signature_trust_level trust_level;
 };
 
 void signature_check_clear(struct signature_check *sigc);