Improve orphaned TLS section handling

ld/

	PR ld/16498
	* emultempl/elf32.em (gld${EMULATION_NAME}_place_orphan): Improve
	orphaned TLS section handling.

ld/testsuite/

	PR ld/16498
	* ld-elf/pr16498a.d: New file.
	* ld-elf/pr16498a.s: Likewise.
	* ld-elf/pr16498a.t: Likewise.
Add another testcase for PR ld/16498

	PR ld/16498
	* ld-elf/pr16498b.d: New file.
	* ld-elf/pr16498b.t: Likewise.
Replace .align with .p2align

	* ld-elf/pr16498a.s: Replace .align with .p2align.
Add .data and .bss refsym symbols

For each object, if it has a nonempty .data or .bss section,
emit a symbol that could cause the startup code to selectively
link in the code to initialize those sections.

* config/tc-msp430.c (msp430_section): Always flag data sections,
regardless of -md.
(msp430_frob_section): New.  Make sure all sections are noticed if
they have content.
(msp430_lcomm): New.  Flag bss if .lcomm is seen.
(msp430_comm): New.  Likewise.
(md_pseudo_table): Add them.
* config/tc-msp430.h (msp430_frob_section): Declare.
(tc_frob_section): Define.