fix(Makefile): remove wildcards in clean target

Be specific and remove only the default files created.

Closes: #303

Signed-off-by: Agathe Porte <agathe.porte@oss.qualcomm.com>

Author: gagath

Makefile

@@ -65,7 +65,7 @@ test: disk-ufs.img
 
 .PHONY: clean
 clean:
-	rm -f disk-ufs.img*
-	rm -f disk-sdcard.img*
-	rm -f rootfs.tar*
+	rm -f disk-ufs.img1 disk-ufs.img2 disk-ufs.img
+	rm -f disk-sdcard.img1 disk-sdcard.img2 disk-sdcard.img
+	rm -f rootfs.tar
 	rm -f dtbs.tar.gz