pwm: Reorder symbols in core.c

pwm: Reorder symbols in core.c

This moves pwm_get() and friends above the functions handling
registration of pwmchips. The motivation is that character device
support needs pwm_get() and pwm_put() and so ideally is defined below
these and when a pwmchip is registered this registers the character
device. So the natural order is

	pwm_get() and friend
	pwm character device symbols
	pwm_chip functions

. The advantage of having these in their natural order is that static
functions don't need to be forward declared.

Note that the diff that git produces for this change some functions are
moved down instead. This is technically equivalent, but not how this
change was created.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/193b3d933294da34e020650bff93b778de46b1c5.1726819463.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>