Fix HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY spelling

Fix HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY spelling

The enumerator HARMLESS_SYMBOL_ALIAS_CHANGE_CATEORY has a spelling
mistake in it. This changes fixes this and also corrects the spelling
of both this and HARMLESS_UNION_CHANGE_CATEORY when output.

	* include/abg-comparison.h (enum diff_category): Rename
	HARMLESS_SYMBOL_ALIAS_CHANGE_CATEORY enumerator to
	HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY.
	* src/abg-comp-filter.cc (categorize_harmless_diff_node): Replace
	use of HARMLESS_SYMBOL_ALIAS_CHANGE_CATEORY enumerator with
	HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY.
	* src/abg-comparison.cc (get_default_harmless_categories_bitmap):
	Replace use of HARMLESS_SYMBOL_ALIAS_CHANGE_CATEORY enumerator
	with HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY.
	(operator<<): In the diff_category overload, replace use of
	HARMLESS_SYMBOL_ALIAS_CHANGE_CATEORY enumerator with
	HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY and output correct
	spelling for both this and HARMLESS_UNION_CHANGE_CATEGORY.
	* tools/abicompat.cc (create_diff_context): Replace use of
	HARMLESS_SYMBOL_ALIAS_CHANGE_CATEORY enumerator with
	HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY.

Signed-off-by: Giuliano Procida <gprocida@google.com>