Update tools/toolchains/mbed_toolchain.py

Co-Authored-By: Graham Hammond <graham.hammond@arm.com>

Author: mark-edgeworth

tools/toolchains/mbed_toolchain.py

@@ -739,7 +739,7 @@ def link_program(self, r, tmp_path, name):
 
         # Absolute path of the final linked file
         if self.config.has_regions:
-            elf = join(tmp_path, tail + '_application.elf')
+            elf = join(new_path, tail + '_application.elf')
             mapfile = join(tmp_path, tail + '_application.map')
         else:
             elf = join(tmp_path, tail + '.elf')