makemake: Extract package name to RPM name mapping into functions

This reintroduces an extra traversal over the specs, but this whole
mess should go away shortly.

Signed-off-by: Euan Harris <euan.harris@citrix.com>
makemake: Start on a test suite

Signed-off-by: Euan Harris <euan.harris@citrix.com>
makemake: Regenerate dependencies automatically in the makefile

makemake.py is now known as specdep.py

Signed-off-by: Euan Harris <euan.harris@citrix.com>