usb: mtu3: remove mtu3_ep0_setup() declaration in mtu3.h

It's defined and only used in the same file, so remove its declaration
in mtu3.h, and make it static

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1622182260-23767-1-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/mtu3/mtu3.h

@@ -422,7 +422,6 @@ int mtu3_config_ep(struct mtu3 *mtu, struct mtu3_ep *mep,
 		int interval, int burst, int mult);
 void mtu3_deconfig_ep(struct mtu3 *mtu, struct mtu3_ep *mep);
 void mtu3_ep_stall_set(struct mtu3_ep *mep, bool set);
-void mtu3_ep0_setup(struct mtu3 *mtu);
 void mtu3_start(struct mtu3 *mtu);
 void mtu3_stop(struct mtu3 *mtu);
 void mtu3_dev_on_off(struct mtu3 *mtu, int is_on);

drivers/usb/mtu3/mtu3_core.c

@@ -536,7 +536,7 @@ static void get_ep_fifo_config(struct mtu3 *mtu)
 		rx_fifo->base, rx_fifo->limit);
 }
 
-void mtu3_ep0_setup(struct mtu3 *mtu)
+static void mtu3_ep0_setup(struct mtu3 *mtu)
 {
 	u32 maxpacket = mtu->g.ep0->maxpacket;
 	u32 csr;