rtlwifi: rtl8192de: Fully initialize curvecount_val

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally writing across neighboring array fields.

The size argument to memset() is bytes, but the array element size
of curvecount_val is u32, so "CV_CURVE_CNT * 2" was only 1/4th of the
contents of curvecount_val. Adjust memset() to wipe full buffer size.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210617171317.3410722-1-keescook@chromium.org