Extend "skip" command to support -file, -gfile, -function, -rfunction.

Extend "skip" command to support -file, -gfile, -function, -rfunction.

gdb/ChangeLog:

	Extend "skip" command to support -file, -gfile, -function, -rfunction.
	* NEWS: Document new features.
	* skip.c: #include "fnmatch.h", "gdb_regex.h".
	(skiplist_entry) <file>: Renamed from filename.
	<function>: Renamed from function_name.
	<file_is_glob, function_is_regexp>: New members.
	<compiled_function_regexp, compiled_function_regexp_is_valid>:
	New members.
	(make_skip_entry): New function.
	(free_skiplist_entry, free_skiplist_entry_cleanup): New functions.
	(make_free_skiplist_entry_cleanup): New function.
	(skip_file_command): Update.
	(skip_function, skip_function_command): Update.
	(compile_skip_regexp): New functions.
	(skip_command): Add support for new options.
	(skip_info): Update.
	(skip_file_p, skip_gfile_p): New functions.
	(skip_function_p, skip_rfunction_p): New functions.
	(function_name_is_marked_for_skip): Update and simplify.
	(_initialize_step_skip): Update.
	* symtab.c: #include "fnmatch.h".
	(compare_glob_filenames_for_search): New function.
	* symtab.h (compare_glob_filenames_for_search): Declare.
	* utils.c (count_path_elements): New function.
	(strip_leading_path_elements): New function.
	* utils.h (count_path_elements): Declare.
	(strip_leading_path_elements): Declare.

gdb/doc/ChangeLog:

	* gdb.texinfo (Skipping Over Functions and Files): Document new
	options to "skip" command.  Update docs of output of "info skip".

gdb/testsuite/ChangeLog:

	* gdb.base/skip.c (test_skip): New function.
	(end_test_skip_file_and_function): New function.
	(test_skip_file_and_function): New function.
	* gdb.base/skip1.c (test_skip): New function.
	(skip1_test_skip_file_and_function): New function.
	* gdb.base/skip.exp: Add tests for new skip options.
	* gdb.base/skip-solib.exp: Update expected output.
	* gdb.perf/skip-command.cc: New file.
	* gdb.perf/skip-command.exp: New file.
	* gdb.perf/skip-command.py: New file.