Create a new flash target for a previously created binary target using
the idf_build_binary or idf_sign_binary function. Specify the new target
name with the TARGET option. The binary image path is stored in the
BINARY_PATH property of the binary target and is set when the binary
target is created using the idf_build_binary or idf_sign_binary
function. Use the NAME option as a prefix for the generated esptool
argument file, and the FLASH option can be used to include the binary
image flashing in the global flash target.
Signed-off-by: Frantisek Hrbata <frantisek.hrbata@espressif.com>