ath9k_hw: Fix possible OOB array indexing in gen_timer_index[] on 64-bit

ath9k_hw: Fix possible OOB array indexing in gen_timer_index[] on 64-bit

commit c90017dd43f0cdb42134b9229761e8be02bcd524 upstream.

debruijn32 (0x077CB531) is used to index gen_timer_index[]
which is an array of 32 u32. Having debruijn32 as unsigned
long on a 64-bit platform  will result in indexing more than 32
in gen_timer_index[] and there by causing a crash. Make it
unsigned to fix this issue.

Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>