tests-usb_device-hid: MSG_KEY_DEVICE_READY is defined twice

[jeromecoutant]

Hi

mbed-os/TESTS/usb_device/hid/main.cpp

Lines 45 to 46 in ffdd543

	#define MSG_KEY_DEVICE_READY "ready"
	#define MSG_KEY_DEVICE_READY "dev_ready"

MSG_KEY_DEVICE_READY is defined twice

Regards,

[0xc0170]

cc @maciejbocianski

[ciarmcom]

Internal Jira reference: https://jira.arm.com/browse/MBOTRIAGE-2417

[0xc0170]

@jeromecoutant Can you send PR fixing it? "dev_ready" should be fine to be used.