Fix memory leaks in error reporting with LOG level

When loglevel is set to LOG, allocated strings used in the error
message would leak. Fix by explicitly pfreeing them.

Author: Ranier Vilela <ranier.vf@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAEudQAqMeE0AHcOsOzZx51Z0eiFJAjhBPRFt+Bxi3ETXWen7ig@mail.gmail.com

Author: danielgustafsson

src/backend/archive/shell_archive.c

@@ -125,9 +125,11 @@ shell_archive_file(ArchiveModuleState *state, const char *file,
 					 errdetail("The failed archive command was: %s",
 							   xlogarchcmd)));
 		}
+		pfree(xlogarchcmd);
 
 		return false;
 	}
+	pfree(xlogarchcmd);
 
 	elog(DEBUG1, "archived write-ahead log file \"%s\"", file);
 	return true;

src/backend/libpq/be-secure-common.c

@@ -85,12 +85,16 @@ run_ssl_passphrase_command(const char *prompt, bool is_server_start, char *buf,
 	}
 	else if (pclose_rc != 0)
 	{
+		char	   *reason;
+
 		explicit_bzero(buf, size);
+		reason = wait_result_to_str(pclose_rc);
 		ereport(loglevel,
 				(errcode_for_file_access(),
 				 errmsg("command \"%s\" failed",
 						command),
-				 errdetail_internal("%s", wait_result_to_str(pclose_rc))));
+				 errdetail_internal("%s", reason)));
+		pfree(reason);
 		goto error;
 	}