Use dynamically linked f2fs executables.

It also reduces the space cost for devices using f2fs (e.g. crosshatch).
/sbin/mkfs.f2fs   722560 => /system/bin/make_f2fs   49568
/sbin/sload.f2fs 1182456 => /system/bin/sload_f2fs 150032

Test: Build and boot recovery on crosshatch. Factory reset.
Test: Install a non-A/B OTA package that formats a f2fs partition.
Change-Id: Ibe70c8d91a1d07e1c78ff9eac19b1f7955800161