Bind defined symbol locally in PIE

Symbols defined in PIE should be bound locally, the same as -shared
-Bsymbolic.

Backport from master

bfd/

	PR ld/19827
	* elf32-i386.c (elf_i386_check_relocs): Bind defined symbol
	locally in PIE.
	(elf_i386_relocate_section): Likewise.
	* elf64-x86-64.c (elf_x86_64_check_relocs): Likewise.
	(elf_x86_64_relocate_section): Likewise.

ld/

	PR ld/19827
	* testsuite/ld-i386/i386.exp: Run PR ld/19827 tests.
	* testsuite/ld-x86-64/x86-64.exp: Likewise.
	* testsuite/ld-i386/pr19827.rd: New file.
	* testsuite/ld-i386/pr19827a.S: Likewise.
	* testsuite/ld-i386/pr19827b.S: Likewise.
	* testsuite/ld-x86-64/pr19827.rd: Likewise.
	* testsuite/ld-x86-64/pr19827a.S: Likewise.
	* testsuite/ld-x86-64/pr19827b.S: Likewise.