i3c/master/mipi-i3c-hci: Fix a potentially infinite loop in 'hci_dat_v1_get_index()'

i3c/master/mipi-i3c-hci: Fix a potentially infinite loop in 'hci_dat_v1_get_index()'

The code in 'hci_dat_v1_get_index()' really looks like a hand coded version
of 'for_each_set_bit()', except that a +1 is missing when searching for the
next set bit.

This really looks odd and it seems that it will loop until 'dat_w0_read()'
returns the expected result.

So use 'for_each_set_bit()' instead. It is less verbose and should be more
correct.

Fixes: 9ad9a52cce28 ("i3c/master: introduce the mipi-i3c-hci driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Nicolas Pitre <npitre@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/0cdf3cb10293ead1acd271fdb8a70369c298c082.1637186628.git.christophe.jaillet@wanadoo.fr