Please remove device-specific hacks from fixup-mountpoints

[makinbacon21]

Adding device- or vendor-specific hacks to platform-agnostic repositories is poor form and detracts from code readability and interoperability. Device family common repos especially would have trouble with such a system. Device hacks should be written in from vendor or device repos--you may need to add a variable to facilitate this. I would recommend something like TARGET_HYBRIS_FSTAB, which could be set from a device-specific repo and provide device-specific fstab locations.