Mount /system in SHW-M110S via adb

To make /system writable
mount -o rw,remount -t ext4 /dev/block/mmcblk0p2 /system

To return /system read-only
mount -o ro,remount -t ext4 /dev/block/mmcblk0p2 /system

Btw, the davlik cache in the Android system is (in most cases) located in /data/dalvik-cache. And from my experience it is usually safe to wipe all files (rm *) inside this folder.