asan: buffer overflows after calling ignore_rest_of_line

operand() is not a place that should be calling ignore_rest_of_line.
ignore_rest_of_line shouldn't increment input_line_pointer if already
at buffer limit.

	* expr.c (operand): Don't call ignore_rest_of_line.
	* read.c (s_mri_common): Likewise.
	(ignore_rest_of_line): Don't increment input_line_pointer if
	already at buffer_limit.