Staging: fbtft: fix memory leak in fbtft_framebuffer_alloc

Staging: fbtft: fix memory leak in fbtft_framebuffer_alloc

In fbtft_framebuffer_alloc the error handling path should take care of
releasing frame buffer after it is allocated via framebuffer_alloc, too.
Therefore, in two failure cases the goto destination is changed to
address this issue.

Fixes: 4119614be47b ("staging: fbtft: core support")
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20190930030949.28615-1-navid.emamdoost@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>