[ARM] PR ld/21402, only override the symbol dynamic decision on undefined weak symbol.

[ARM] PR ld/21402, only override the symbol dynamic decision on undefined weak symbol.

Similar as aarch64 backend, arm backend only overrides the decision on undefined
weak symbols. arm backend part already emits necessary relative relocation for
this case.

bfd/

	PR ld/21402
	* elf32-arm.c (allocate_dynrelocs_for_symbol): Only make undefined weak
	symbols into dynamic.

ld/

	PR ld/21402
	* testsuite/ld-arm/tls-app.d: Update address.
	* testsuite/ld-arm/tls-app.r: Remove relocations.
	* testsuite/ld-arm/unresolved-1-dyn.d: Update.