rust: pwm: Simplify to_result call sites and unsafe blocks

rust: pwm: Simplify to_result call sites and unsafe blocks

Remove unnecessary temporary variables around to_result() calls and move
trailing semicolons outside unsafe blocks to improve readability and
produce cleaner rustfmt output.

No functional change intended.

Signed-off-by: Kari Argillander <kari.argillander@gmail.com>
Acked-by: Michal Wilczynski <m.wilczynski@samsung.com>
Link: https://patch.msgid.link/20260102-pwm-rust-v2-2-2702ce57d571@gmail.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>