drivers/video/aty/radeon_base.c: notify user if sysfs_create_bin_file() failed

Current kernel builds warn about:
drivers/video/aty/radeon_base.c: In function 'radeonfb_pci_register':
drivers/video/aty/radeon_base.c:2334: warning: ignoring return value of 'sysfs_create_bin_file', declared with attribute warn_unused_result
drivers/video/aty/radeon_base.c:2336: warning: ignoring return value of 'sysfs_create_bin_file', declared with attribute warn_unused_result

Do minimal checking of these functions and issue a warning if either
fails.  They don't seem to be critical..

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>