properly parenthesize two macros

properly parenthesize two macros

I happened to notice that a couple of macros in target.h weren't
properly using parens and as a result had a strange definition.

This patch adds the parens and then fixes the macros to be written as
must have been intended.

Tested by rebuilding.
I'm pushing this as obvious.

2014-07-25  Tom Tromey  <tromey@redhat.com>

	* target.h (target_stopped_data_address)
	(target_watchpoint_addr_within_range): Use "->", not ".".  Fix
	parentheses.