ocfs2: add spinlock protection when dealing with lockres->purge.
ocfs2: add spinlock protection when dealing with lockres->purge.

when we check/modify lockres->purge, we should with the protection of lockres->spinlock.
in dlm_purge_lockres(), the checking/modifying is not with the protectin.
this patch fixes it.

Signed-off-by: Wengang Wang <c9b5a2b41362ea5da1af6808c2371472f6e02870@oracle.com>
Signed-off-by: Joel Becker <823d0e2e55da83c1616b20ae9a15f9456fa076e5@oracle.com>

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