of/irq: Avoid calling list_first_entry() for empty list
of/irq: Avoid calling list_first_entry() for empty list

list_first_entry() expects the list is not empty, we need to check if list is
empty before calling list_first_entry(). Thus use list_first_entry_or_null()
instead of list_first_entry().

Signed-off-by: Axel Lin <b6ffd6973e972cb999e8e535ab74da7fee0c035f@ingics.com>
Signed-off-by: Grant Likely <9069e6f5a2b566e2674a0ba1e2bf39c12c195fad@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs