mfd: ipaq-micro: Remove unused variable i in micro_rx_msg()

mfd: ipaq-micro: Remove unused variable i in micro_rx_msg()

There is a warning reported by kernel test robot:

drivers/mfd/ipaq-micro.c:81:6: warning: unused variable ‘i’ [-Wunused-variable]

Since the commit 92d82d76c842 ("mfd: ipaq-micro: Use %*ph for printing
hexdump of a small buffer"), the variable 'i' is unused. Remove it to
silence the warning.

Reported-by: kernelci.org bot <bot@kernelci.org>
Closes: https://lore.kernel.org/all/64c8aeac.170a0220.e3234.2745@mx.google.com/
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Link: https://lore.kernel.org/r/20230817114505.1810920-1-lizetao1@huawei.com
Signed-off-by: Lee Jones <lee@kernel.org>