stm32 usb compile failure

[rm5248]

When compiling the STM32 USB driver, I get a compile error:

CC:  chip/stm32_otghsdev.c chip/stm32_otghsdev.c: In function 'stm32_ep_allocbuffer':
chip/stm32_otghsdev.c:4367:33: error: 'privep' undeclared (first use in this function); did you mean 'pipe2'?
   usbtrace(TRACE_EPALLOCBUFFER, privep->epphy);
                                 ^~~~~~
                                 pipe2
chip/stm32_otghsdev.c:4367:33: note: each undeclared identifier is reported only once for each function it appears in
chip/stm32_otghsdev.c: In function 'stm32_ep_freebuffer':
chip/stm32_otghsdev.c:4388:32: error: 'privep' undeclared (first use in this function); did you mean 'pipe2'?
   usbtrace(TRACE_EPFREEBUFFER, privep->epphy);
                                ^~~~~~
                                pipe2

code: https://github.com/apache/nuttx/blob/master/arch/arm/src/stm32/stm32_otghsdev.c#L4367

Changing privep to ep does not fix the compile error. I'm not sure what this is supposed to be in the first place.

[acassis]

@rm5248 good finding!

Please use: ((struct stm32_ep_s *)ep)->epphy