add sofia_sla.c to windows build

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@11564 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/mod/endpoints/mod_sofia/mod_sofia.2008.vcproj

@@ -176,6 +176,10 @@
 			RelativePath=".\sofia_reg.c"
 			>
 		</File>
+		<File
+			RelativePath=".\sofia_sla.c"
+			>
+		</File>
 	</Files>
 	<Globals>
 	</Globals>

src/mod/endpoints/mod_sofia/mod_sofia.vcproj

@@ -178,6 +178,10 @@
 			RelativePath=".\sofia_reg.c"
 			>
 		</File>
+		<File
+			RelativePath=".\sofia_sla.c"
+			>
+		</File>
 	</Files>
 	<Globals>
 	</Globals>