Adding USB manufacturer to boards desc

Signed-off-by: Thibaut VIARD <thibaut.viard@atmel.com>

boards.txt

@@ -10,6 +10,7 @@ arduino_zero_edbg.upload.native_usb=false
 arduino_zero_edbg.build.mcu=cortex-m0plus
 arduino_zero_edbg.build.f_cpu=48000000L
 arduino_zero_edbg.build.usb_product="Arduino Zero"
+arduino_zero_edbg.build.usb_manufacturer="Arduino LLC"
 arduino_zero_edbg.build.board=SAMD_ZERO
 arduino_zero_edbg.build.core=arduino
 arduino_zero_edbg.build.extra_flags=-D__SAMD21G18A__ {build.usb_flags}
@@ -34,6 +35,7 @@ arduino_zero_native.upload.native_usb=true
 arduino_zero_native.build.mcu=cortex-m0plus
 arduino_zero_native.build.f_cpu=48000000L
 arduino_zero_native.build.usb_product="Arduino Zero"
+arduino_zero_native.build.usb_manufacturer="Arduino LLC"
 arduino_zero_native.build.board=SAMD_ZERO
 arduino_zero_native.build.core=arduino
 arduino_zero_native.build.extra_flags=-D__SAMD21G18A__ {build.usb_flags}