Revert "BUILDING: Add needed misc fixes for SFOS 3.4 building"

These are no longer needed after sailfishos-oneplus5/droid-hal-device@b1b1a8f.

This reverts commit 7b10e6e.

BUILDING.md

@@ -68,31 +68,11 @@ HA_BUILD $ mka hybris-boot
 
 ## Building SFOS packages & rootfs<a name="building-sfos-packages-rootfs"></a>
 
-Before beginning, run the following to avoid a few errors while building and pulling repo updates:
-```
-croot
-cd external/libhybris
-git checkout master
-cd -
-cd hybris/mw/sailfish-fpd-community
-git checkout master
-cd -
-```
-
 To pull updates and start (re)building all locally required SFOS packages & the rootfs, run the following command (full build takes ~20 minutes for me):
 ```
 PLATFORM_SDK $ build_all_packages
 ```
 
-For now here's also a temporary "fix" for `repo problem: nothing provides sailfish-fpd-community needed by pattern:jolla-configuration-...`:
-```
-croot
-cp droid-local-repo/$DEVICE/sailfish-fpd-community/droid-*.rpm /tmp
-bp -b hybris/mw/sailfish-fpd-community -s rpm/sailfish-fpd-community.spec
-mv /tmp/droid-*.rpm droid-local-repo/$DEVICE/sailfish-fpd-community/
-bp -vi
-```
-
 As the rootfs `mic` build command line is now included in `build_packages.sh` steps, this is all you need to get a rather tiny (~380 MB) flashable SFOS zip file! Look into the [flashing guide](FLASHING.md) on how to proceed afterwards.
 
 When just droid configs have been modified, `build_device_configs` will be enough. Same goes for droid HAL stuff with `build_droid_hal` instead. Building with these commands instead will be substantially faster than rebuilding everything (which is unnecessary 99% of the time anyways).