Documentation: dpll: wrap DPLL_CMD_PIN_GET output in a code block

DPLL_CMD_PIN_GET netlink command output for mux-type pins looks ugly
with normal paragraph formatting. Format it as a code block instead.

Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://lore.kernel.org/r/20230928052708.44820-3-bagasdotme@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>