usb: ehci: Fix warning on aarch64

usb: ehci: Fix warning on aarch64

Fix the following warning on aarch64 introduced by using p2v/v2p
functions in the code:

In file included from ./arch/arm/include/asm/byteorder.h:29:0,
                 from include/compiler.h:125,
                 from include/image.h:19,
                 from include/common.h:88,
                 from drivers/usb/host/ehci-hcd.c:10:
drivers/usb/host/ehci-hcd.c: In function ‘ehci_td_buffer’:
drivers/usb/host/ehci-hcd.c:250:49: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
   td->qt_buffer[idx] = cpu_to_hc32(virt_to_phys((void *)addr));
                                                 ^
include/linux/byteorder/little_endian.h:34:51: note: in definition of macro ‘__cpu_to_le32’
 #define __cpu_to_le32(x) ((__force __le32)(__u32)(x))
                                                   ^
drivers/usb/host/ehci-hcd.c:250:24: note: in expansion of macro ‘cpu_to_hc32’
   td->qt_buffer[idx] = cpu_to_hc32(virt_to_phys((void *)addr));

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Tom Rini <trini@konsulko.com>