PR27228, .reloc wrong symbol emitted for undefined local symbol

PR27228, .reloc wrong symbol emitted for undefined local symbol

Local symbols are of course supposed to be defined by their object
file, but in other cases a local symbol is promoted to global by gas
if undefined and referenced.  This patch stops gas wrongly replacing a
local undefined symbol with the undefined section symbol, resulting in
a .reloc undefined local symbol being emitted as global.

	PR 27228
	* write.c (resolve_reloc_expr_symbols): Don't assume local symbol
	is defined.