Remove duplicated and incorrect fetching of 'map_bump' attributes in obj plugin
Remove duplicated and incorrect fetching of 'map_bump' attributes in obj plugin

Parsing the key 'map_bump' was processed in the block, where the attributes
for 'bump' are extracted and results into having parts of the key in the
extracted filename, generating an invalid filename.

The mentioned string compare could be removed without loosing any features,
because the key 'map_bump' is parsed correctly some lines below.

scrawl/osg,openscenegraph/osg,scrawl/osg,openscenegraph/osg,scrawl/osg,openscenegraph/osg,openscenegraph/osg,scrawl/osg