ecryptfs: Remove unnecessary variable initialization
ecryptfs: Remove unnecessary variable initialization

Removes unneeded variable initialization in ecryptfs_read_metadata(). Also adds
a small comment to help explain metadata reading logic.

[93eeee00a2beb1fbd6106ad8f59025f171ca91c6@canonical.com: Pulled out of for-stable patch and wrote commit msg]
Signed-off-by: Tim Gardner <c65a040f7f664378353fb65fc3553df208a14f68@canonical.com>
Signed-off-by: Tyler Hicks <93eeee00a2beb1fbd6106ad8f59025f171ca91c6@canonical.com>

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