Track dependencies in linkerscripts (gcc toolchain)

It would be useful if Qbs could scan and track dependencies in linkerscripts (gcc-based toolchains mostly).

The linkerscripts might contain INCLUDE statements that include other scripts. Currently Qbs will not link again as a result of one of these being modified.

The ld documentation says:

INCLUDE filename
Include the linker script filename at this point.  
The file will be searched for in the current directory, and in any directory specified with the -L option.  You can nest calls to INCLUDE up to
10 levels deep.

This is mostly useful when working on "bare metal" embedded devices.