tx25: fix linker file for newer ld support

older ld emitted all ELF relocations in input sections named
.rel.dyn, whereas newer ld uses names of the form .rel*. The
linker script only collected .rel.dyn input sections. Rewrite
to collect all .rel* input sections.

Signed-off-by: Albert Aribaud <albert.aribaud@free.fr>