brcmfmac: Fix incorrect casting of 64 bit physical address.

The physical addresses being used by pcie and msgbuf were using
a cast to long, which incorrectly caused it to limit the address
to 32bit. Now explicit u64 is used where needed.

Reviewed-by: Arend Van Spriel <arend@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>