In mboot, the ability to override the USB vendor/product id's was added
back in 5688c9ba09. However, when the main
firmware is turned into a DFU file the default VID/PID are used there.
pydfu.py doesn't care about this but dfu-util does and prevents its use
when the VID/PID don't match.
This commit exposes BOOTLOADER_DFU_USB_VID/PID as make variables, for use
on either command line or mpconfigboard.mk, to set VID/PID in both mboot
and DFU files.
Add -Wdouble-promotion and -Wfloat-conversion for most ports to ban out
implicit floating point conversions, and add extra Travis builds using
MICROPY_FLOAT_IMPL_FLOAT to uncover warnings which weren't found
previously. For the unix port -Wsign-comparison is added as well but only
there since only clang supports this but gcc doesn't.
A recent version of arm-none-eabi-gcc (8.2.0) will warn about unused packed
attributes in USB_WritePacket and USB_ReadPacket. This patch suppresses
such warnings for this file only.
Mboot is a custom bootloader for STM32 MCUs. It can provide a USB DFU
interface on either the FS or HS peripherals, as well as a custom I2C
bootloader interface.
