Upgrade nanopb to v0.4.8

Upgrade the nanopb to 0.4.8 and add the following fixes:
  - remove the nanopb patch as it has become obsolete.
  - stop using the nanopb protoc wrapper when building the generator as
    this seems to cause build issues.
  - use the new nanopb_PYTHON_INSTDIR_OVERRIDE variable to set the
    install location for the generator. Modify TS cmake script to search
    the generator in the install content instead of the nanopb source.
  - pass discovered python settings to nanopb build using the initial
    cache. This speeds up the build and allows easier control of python
    discovery for integration systems.
  - solve nanopb os.makedirs race by creating the directory from cmake.

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Gyorgy Szing <gyorgy.szing@arm.com>
Change-Id: Idc36cf9a446493e4eb994fc9808f96277f11c0bc
3 files changed