USB Device Descriptor Max Power is not configurable #504

[Props3D]

Looking at Adafruit_USBD_Device.cpp, there's a define macro for the Max Power but it's never used.

at line 85:

#ifndef USB_CONFIG_POWER
#define USB_CONFIG_POWER 100
#endif

At line 186, the power is hardcoded to 100:

  uint8_t const dev_cfg[sizeof(tusb_desc_configuration_t)] = {
      TUD_CONFIG_DESCRIPTOR(1, 0, 0, sizeof(tusb_desc_configuration_t),
                            TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP | TU_BIT(7),
                            100),
  };

I simply replaced the 100 with USB_CONFIG_POWER.

[SmittyHalibut]

I almost added this change to #493 too. I like it.