sbchooser: fix load_secdb_from_file returning fd instead of rc

When read_file() fails, returning fd instead of rc causes callers to
miss the error since fd is a non-negative integer after close(). Fix
by returning rc.

Signed-off-by: Aditya Nair <adnair@redhat.com>

Author: adsuna

src/sbchooser-db.c

@@ -256,7 +256,7 @@ load_secdb_from_file(const char * const filename, efi_secdb_t **secdbp)
 	close(fd);
 	if (rc < 0) {
 		efi_error("Could not read file \"%s\": %m", filename);
-		return fd;
+		return rc;
 	}
 	data_size -= 1;