Extend show error/warning as Link

PR #6270 added a parameter which allows the user to decide in case of an error or warning to print the output as a link.
This extension of this option also prints the ARM-GCC output in a link format.

tools/notifier/term.py

@@ -86,7 +86,7 @@ class TerminalNotifier(Notifier):
             event['severity'] = event['severity'].title()
 
             if PRINT_COMPILER_OUTPUT_AS_LINK:
-                event['file'] = getcwd() + event['file'].strip('.')
+                event['file'] = abspath(event['file'])
                 return '[{severity}] {file}:{line}:{col}: {message}'.format(
                     **event)
             else:

tools/toolchains/__init__.py

@@ -18,7 +18,7 @@ from __future__ import print_function, division, absolute_import
 
 import re
 import sys
-from os import stat, walk, getcwd, sep, remove
+from os import stat, walk, getcwd, sep, remove, path
 from copy import copy
 from time import time, sleep
 from shutil import copyfile
@@ -433,7 +433,7 @@ class mbedToolchain:
         self.build_all = False
 
         # Build output dir
-        self.build_dir = build_dir
+        self.build_dir = path.abspath(build_dir) if PRINT_COMPILER_OUTPUT_AS_LINK else build_dir
         self.timestamp = time()
 
         # Number of concurrent build jobs. 0 means auto (based on host system cores)
@@ -988,6 +988,8 @@ class mbedToolchain:
         _, ext = splitext(source)
         ext = ext.lower()
         
+        source = abspath(source) if PRINT_COMPILER_OUTPUT_AS_LINK else source
+
         if ext == '.c' or  ext == '.cpp':
             base, _ = splitext(object)
             dep_path = base + '.d'