pth: Fix case where ${B} != ${S}

Ensure the autotools commands are executed in ${S} to allow out of tree
builds to work.

(From OE-Core rev: afeea8a616ea43553a7cd6c160d5f8b23ddcfa38)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-support/pth/pth_2.0.7.bb

@@ -23,7 +23,7 @@ PARALLEL_MAKE=""
 inherit autotools binconfig pkgconfig
 
 do_configure() {
-	gnu-configize
-	autoconf
+	( cd ${S}; gnu-configize )
+	( cd ${S}; autoconf )
 	oe_runconf
 }