Leandro Ribeiro authored Nov 22, 2019 and Daniel Stone committed Nov 23, 2019

Since commit 28d26483 ("build: bump libdrm requirement to newer version
(2.4.83)"), all supported libdrm versions provide modifier formats,
atomic API and blob formats. Remove ifdef checks (HAVE_DRM_ADDFB2_MODIFIERS,
HAVE_DRM_ATOMIC, HAVE_DRM_FORMATS_BLOB) to improve the code and make it
simpler.

Signed-off-by: Leandro Ribeiro <leandrohr@riseup.net>