Add maximum data size and regex, to present "Global variables use..." during verify

Author: ollie1400

boards.txt

@@ -7,6 +7,7 @@ arduino_due_x_dbg.pid.1=0x003d
 arduino_due_x_dbg.upload.tool=bossac
 arduino_due_x_dbg.upload.protocol=sam-ba
 arduino_due_x_dbg.upload.maximum_size=524288
+arduino_due_x_dbg.upload.maximum_data_size=98304
 arduino_due_x_dbg.upload.use_1200bps_touch=true
 arduino_due_x_dbg.upload.wait_for_upload_port=false
 arduino_due_x_dbg.upload.native_usb=false
@@ -31,6 +32,7 @@ arduino_due_x.pid.1=0x003e
 arduino_due_x.upload.tool=bossac
 arduino_due_x.upload.protocol=sam-ba
 arduino_due_x.upload.maximum_size=524288
+arduino_due_x_dbg.upload.maximum_data_size=98304
 arduino_due_x.upload.use_1200bps_touch=true
 arduino_due_x.upload.wait_for_upload_port=true
 arduino_due_x.upload.native_usb=true

platform.txt

@@ -90,6 +90,7 @@ recipe.output.save_file={build.project_name}.{build.variant}.bin
 ## Compute size
 recipe.size.pattern="{compiler.path}{compiler.size.cmd}" -A "{build.path}/{build.project_name}.elf"
 recipe.size.regex=\.text\s+([0-9]+).*
+recipe.size.regex.data=^(?:\.data|\.bss)\s+([0-9]+).*
 
 
 # SAM3 Uploader tools