Add NLM compiler flags around cancel_all_nlm_blocked

Signed-off-by: Allison Henderson <achender@vnet.linux.ibm.com>
Add EROFS to posix2fsal_error

Signed-off-by: Allison Henderson <achender@vnet.linux.ibm.com>
Do not check/fail on getattr error for a file that is unlinked in cache_inode_remove

Signed-off-by: Allison Henderson <achender@vnet.linux.ibm.com>