Commit a934a57a42f6 ("scripts/misc-check: check missing #include
<linux/export.h> when W=1") introduced a new check that is producing
the following warning:
drivers/net/wireless/ath/ath12k/core.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
Add the missing #include to satisfy the check.
Signed-off-by: Jeff Johnson <jeff.johnson@xxxxxxxxxxxxxxxx>