added host set_config driver

to resolve control conflict with SET_CONFIGURE for class driver
- open will be called to open endpoint only
- set_config called later to initialized class driver

src/class/msc/msc_host.h

@@ -125,6 +125,7 @@ void tuh_msc_unmounted_cb(uint8_t dev_addr);
 
 void msch_init(void);
 bool msch_open(uint8_t rhport, uint8_t dev_addr, tusb_desc_interface_t const *itf_desc, uint16_t *p_length);
+bool msch_set_config(uint8_t dev_addr, uint8_t itf_num);
 bool msch_xfer_cb(uint8_t dev_addr, uint8_t ep_addr, xfer_result_t event, uint32_t xferred_bytes);
 void msch_close(uint8_t dev_addr);