bnxt_en: Refactor bnxt_free_ctx_mem()

bnxt_en: Refactor bnxt_free_ctx_mem()

Add a new function bnxt_free_one_ctx_mem() to free one context
memory type.  bnxt_free_ctx_mem() now calls the new function in
the loop to free each context memory type.  There is no change in
behavior.  Later patches will further make use of the new function.

Signed-off-by: Hongguang Gao <hongguang.gao@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Link: https://patch.msgid.link/20241115151438.550106-4-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>