usb: host: xhci-omap: Remove redundant board_usb_init and board_usb_cleanup functions

board_usb_init()/_cleanup() should be in board files and don't have
a place in the xhci-omap driver. Weak versions for
board_usb_init()/_cleanup() already exist in common/usb.c
(for host mode) and drivers/usb/gadget/g_dnl.c (for gadget mode).

Therefore, remove init and cleanup functions from xhci-omap and
implement them in the board files.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/board/ti/dra7xx/evm.c b/board/ti/dra7xx/evm.c
index 6ecf971..519475e 100644
--- a/board/ti/dra7xx/evm.c
+++ b/board/ti/dra7xx/evm.c
@@ -907,7 +907,7 @@
 	.index = 1,
 };
 
-int omap_xhci_board_usb_init(int index, enum usb_init_type init)
+int board_usb_init(int index, enum usb_init_type init)
 {
 	enable_usb_clocks(index);
 	switch (index) {
@@ -944,7 +944,7 @@
 	return 0;
 }
 
-int omap_xhci_board_usb_cleanup(int index, enum usb_init_type init)
+int board_usb_cleanup(int index, enum usb_init_type init)
 {
 	switch (index) {
 	case 0: