fbdev: ssd1307fb: fix potential page leak in ssd1307fb_probe()

fbdev: ssd1307fb: fix potential page leak in ssd1307fb_probe()

[ Upstream commit 164312662ae9764b83b84d97afb25c42eb2be473 ]

The page allocated for vmem using __get_free_pages() is not freed on the
error paths after it. Fix that by adding a corresponding __free_pages()
call to the error path.

Fixes: facd94bc458a ("fbdev: ssd1307fb: Allocate page aligned video memory.")
Signed-off-by: Abdun Nihaal <nihaal@cse.iitm.ac.in>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>