ipaccess: Fix a resource leak in case the stat is failing

Close the file when the stat is failing.

Fixes: Coverity CID 1040711

openbsc/src/ipaccess/ipaccess-config.c

@@ -743,6 +743,7 @@ static void analyze_firmware(const char *filename)
 	/* verify the file */
 	if (fstat(fd, &stat) == -1) {
 		perror("Can not stat the file");
+		close(fd);
 		return;
 	}