Change linking script options to allow user defined linker scripts

Change linking script options to allow user defined linker scripts

A user may change the linker script for his purposes. This patch
removes warnings when he does so.

The default linker script can now be overridden by changing
LD_FLAGS in user makefile with the following option:
-Wl,-T path/to/linker_script.ld

git-svn-id: https://src.develer.com/svnoss/bertos/trunk@4641 38d2e660-2303-0410-9eaa-f027e97ec537