staging: r8188eu: Fix while-loop that iterates only once

The while-loop only iterates once becase the post increment test of count
being non-zero is false on the first iteration because count is zero. Fix
this by using a for-loop instead. Static analysis found the issue on the
count > POLLING_LLT_THRESHOLD check always being false since the loop
currently just iterates once.

Thanks to David Laight for suggesting using for-loop instead to improve
the readability of the fix.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20210630065647.5641-1-colin.king@canonical.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>