package/ninja: change package type to host-cmake

package/ninja: change package type to host-cmake

Ninja 1.10.0 now supports cmake as a build system. This change makes the make
file much more straightforward.

The host-python2 dependency is no longer needed as it is no longer
used during the build. We however need to keep install commands as
there is no installation step planned in CMakeLists.txt.

Signed-off-by: Adam Duskett <aduskett@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>