xilinx-usbps: Initialize ehci hcd before using it

xilinx-usbps: Initialize ehci hcd before using it

In ehci_xusbps_setup ehci_halt is called before ehci_init. This means that the
initial ehci_halt call is working on a not completely initialized ehci hcd
struct, which might cause undefined behavior. So make sure to call ehci_init
before calling ehci_halt.

This fixes also the following lockdep warning:

	INFO: trying to register non-static key.
	the code is fine but needs lockdep annotation.
	turning off the locking correctness validator.
	[<c001355c>] (unwind_backtrace+0x0/0xe0) from [<c005c6c0>] (__lock_acquire+0x1ac/0x19c0)
	[<c005c6c0>] (__lock_acquire+0x1ac/0x19c0) from [<c005e394>] (lock_acquire+0x60/0x74)
	[<c005e394>] (lock_acquire+0x60/0x74) from [<c034843c>] (_raw_spin_lock_irq+0x50/0x60)
	[<c034843c>] (_raw_spin_lock_irq+0x50/0x60) from [<c02202e8>] (ehci_halt+0x14/0xd8)
	[<c02202e8>] (ehci_halt+0x14/0xd8) from [<c022532c>] (ehci_xusbps_setup+0x58/0x41c)
	[<c022532c>] (ehci_xusbps_setup+0x58/0x41c) from [<c020f828>] (usb_add_hcd+0x194/0x5c0)
	[<c020f828>] (usb_add_hcd+0x194/0x5c0) from [<c0223e28>] (ehci_xusbps_drv_probe+0x158/0x1e0)
	[<c0223e28>] (ehci_xusbps_drv_probe+0x158/0x1e0) from [<c01c84dc>] (platform_drv_probe+0x14/0x18)
	...

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>