Default value for libiconv in target-supports.exp?

[David Edelsohn]

>>>>> Mark Mitchell writes:

Mark> In the past, if libiconv wasn't set in site.exp, 
Mark> target_supports.exp:check_iconv_available would crash.  So, I changed it 
Mark> to default to "-liconv".

Mark> On GNU/Linux, that's not a very good default, since iconv is in libc. 
Mark> The same seems to hold on Solaris and HP-UX.

Mark> Does anyone have opinions about what the default should be?

	It is deparate on AIX.  Is there any way that the testsuite can
pick up the value from the Makefile?

David