d-demangle.c (dlang_call_convention): Return NULL if have reached the end of the...

d-demangle.c (dlang_call_convention): Return NULL if have reached the end of the symbol, but expected something to read.

libiberty/ChangeLog:

2015-05-16  Iain Buclaw  <ibuclaw@gdcproject.org>

	* d-demangle.c (dlang_call_convention): Return NULL if have reached the
	end of the symbol, but expected something to read.
	(dlang_attributes): Likewise.
	(dlang_function_type): Likewise.
	(dlang_type): Likewise.
	(dlang_identifier): Likewise.
	(dlang_value): Likewise.

From-SVN: r223241