ionic: convert Rx queue buffers to use page_pool

Our home-grown buffer management needs to go away and we need
to be playing nicely with the page_pool infrastructure.  This
converts the Rx traffic queues to use page_pool.

Also, since ionic_rx_buf_size() was removed, redefine
IONIC_PAGE_SIZE to account for IONIC_MAX_BUF_LEN being the
largest allowed buffer to prevent overflowing u16 variables,
which could happen when PAGE_SIZE is defined as >= 64KB.

include/linux/minmax.h:93:37: warning: conversion from 'long unsigned int' to 'u16' {aka 'short unsigned int'} changes value from '65536' to '0' [-Woverflow]

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Link: https://patch.msgid.link/20240906232623.39651-7-brett.creeley@amd.com


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