WINGs: correct possible null pointer dereference
As reported by cppcheck:
[WINGs/array.c:129] -> [WINGs/array.c:131]: (warning) Possible null pointer dereference: array - otherwise it is redundant to check it against null.
[WINGs/array.c:151] -> [WINGs/array.c:153]: (warning) Possible null pointer dereference: array - otherwise it is redundant to check it against null.
[WINGs/array.c:170] -> [WINGs/array.c:172]: (warning) Possible null pointer dereference: array - otherwise it is redundant to check it against null.
This patch is checking that the var name 'array' exists.