Make skip without argument skip the current inline function

Make skip without argument skip the current inline function

Previously always the outermost function block was used, but
since skip is now able to skip over inline functions it is more
natural to skip the inline function that the program is currently
executing.

gdb:
2020-01-14  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* skip.c (skip_function_command): Make skip w/o arguments use the
	name of the inlined function if pc is inside any inlined function.

gdb/testsuite:
2020-01-14  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* gdb.base/skip-inline.exp: Extend test.