ath10k: Fix compilation issue

Fix below compilation error with clang
warning: address of array 'arg->ie' will always evaluate
to 'true' [-Wpointer-bool-conversion].

Change-Id: I83b3f584813720ded1c9c986f9aeaa3db1d71fcf
Signed-off-by: Swetha Chikkaboraiah <schikk@codeaurora.org>