usb-ehci: trace state machine changes

Add functions to get and set the current state of the state machine,
add tracepoints there to trace state transitions.  Add support for
traceing the queue heads and transfer descriptors as we look at them.

Drop a few DPRINTFs and all DPRINTF_ST lines, they are obsolete now.

No change in behavior.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

trace-events

@@ -199,6 +199,10 @@ disable usb_ehci_reset(void) "=== RESET ==="
 disable usb_ehci_mmio_readl(uint32_t addr, const char *str, uint32_t val) "rd mmio %04x [%s] = %x"
 disable usb_ehci_mmio_writel(uint32_t addr, const char *str, uint32_t val, uint32_t oldval) "wr mmio %04x [%s] = %x (old: %x)"
 disable usb_ehci_usbsts(const char *sts, int state) "usbsts %s %d"
+disable usb_ehci_state(const char *schedule, const char *state) "%s schedule %s"
+disable usb_ehci_qh(uint32_t addr, uint32_t next, uint32_t c_qtd, uint32_t n_qtd, uint32_t a_qtd, int rl, int mplen, int eps, int ep, int devaddr, int c, int h, int dtc, int i) "QH @ %08x: next %08x qtds %08x,%08x,%08x - rl %d, mplen %d, eps %d, ep %d, dev %d, c %d, h %d, dtc %d, i %d"
+disable usb_ehci_qtd(uint32_t addr, uint32_t next, uint32_t altnext, int tbytes, int cpage, int cerr, int pid, int ioc, int active, int halt, int babble, int xacterr) "QH @ %08x: next %08x altnext %08x - tbytes %d, cpage %d, cerr %d, pid %d, ioc %d, active %d, halt %d, babble %d, xacterr %d"
+disable usb_ehci_itd(uint32_t addr, uint32_t next) "ITD @ %08x: next %08x"
 
 # hw/usb-desc.c
 disable usb_desc_device(int addr, int len, int ret) "dev %d query device, len %d, ret %d"