c++: Fix coroutines.cc build for nvptx-none target

When building offloading cross-compiler from x86_64-linux to nvptx-none, the
build fails with:
../../gcc/cp/coroutines.cc: In function 'tree_node* get_fn_local_identifier(tree, const char*)':
../../gcc/cp/coroutines.cc:2255:12: error: expected ';' before 'char'
 2255 |   sep = "$"
      |            ^
      |            ;
......
 2262 |   char *an;
      |   ~~~~

2020-01-18  Jakub Jelinek  <jakub@redhat.com>

	* coroutines.cc (get_fn_local_identifier): Fix NO_DOT_IN_LABEL
	but non-NO_DOLLAR_IN_LABEL case build.

gcc/cp/ChangeLog

+2020-01-18  Jakub Jelinek  <jakub@redhat.com>
+
+	* coroutines.cc (get_fn_local_identifier): Fix NO_DOT_IN_LABEL
+	but non-NO_DOLLAR_IN_LABEL case build.
+
 2020-01-18  Iain Sandoe  <iain@sandoe.co.uk>
 
 	* Make-lang.in: Add coroutines.o.

gcc/cp/coroutines.cc

@@ -2252,7 +2252,7 @@ get_fn_local_identifier (tree orig, const char *append)
   sep = ".";
 #else
 #ifndef NO_DOLLAR_IN_LABEL
-  sep = "$"
+  sep = "$";
 #else
   sep = "_";
   pfx = "__";