csky: Don't generate unnecessary dynamic tags

Dynamic tags, DT_JMPREL, PLTREL and PLTRELSZ, are needed only if there
are relocation entries for PLT.  Don't generate them if there are no
relocation entries for PLT.

bfd/

	PR ld/26083
	* elf32-csky.c (csky_elf_size_dynamic_sections): Call
	_bfd_elf_add_dynamic_tags.

ld/

	PR ld/26083
	* testsuite/ld-csky/tls-ie-v1.d: Updated.
	* testsuite/ld-csky/tls-ie.d: Likewise.