adb: fix build on glibc systems

Recent changes to adb_walk_adb.c added use of 'PRIu64' which requires
to include inttypes.h on glibc systems.

Fixes: c5d8d286 ("adb: implement ADB_BLOCK_EXT flavor for large files")

src/adb_walk_adb.c

@@ -2,6 +2,7 @@
 
 #include <stdio.h>
 #include <unistd.h>
+#include <inttypes.h>
 #include "apk_adb.h"
 #include "apk_applet.h"
 #include "apk_print.h"