Move bootanimation selection to its own makefile.

Proposed by Evan (@linuxman94).

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>

Change-Id: I43a80a604fe70c21ef108c0af735122fac6ebc82
New PA4+ Bootanimations

big thanks to @espen96 & @MinedCraftian for their effort! Great talent!

Their contacts:
Espen: espen96@gmail.com
Leonard: leonardleijenhorst@gmail.com

Signed-off-by: Andre Saddler <dresadd09691@gmail.com>