loopdev: remove an user triggerable oops
loopdev: remove an user triggerable oops

When loopdev is built as module and we pass an invalid parameter,
loop_init() will return directly without deregister misc device, which
will cause an oops when insert loop module next time because we left some
garbage in the misc device list.

Test case:
sudo modprobe loop max_part=1024
(failed due to invalid parameter)
sudo modprobe loop
(oops)

Clean up nicely to avoid such oops.

Signed-off-by: Guo Chao <e958ec5a56cd9794647c3623b3aa5a85122e74a5@linux.vnet.ibm.com>
Cc: Alexander Viro <de609eb4d5d70b1d38ec6642adbfc33a2781f63c@zeniv.linux.org.uk>
Cc: Guo Chao <e958ec5a56cd9794647c3623b3aa5a85122e74a5@linux.vnet.ibm.com>
Cc: M. Hindess <da819f9b4063211f032bf03c5f98d7fea139fe81@uk.ibm.com>
Cc: Nikanth Karthikesan <e876309828e3f41803de99641e5858aebdf88b24@suse.de>
Cc: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@kernel.dk>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@kernel.dk>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs