qla2xxx: Avoid that sparse complains about context imbalances

Surround conditional locking statements with "#ifndef __CHECKER__" /
"#endif" to hide these for the sparse static source code analysis
tool.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>