patch 9.0.0635: build error and compiler warnings

Problem:    Build error and compiler warnings.
Solution:   Add missing change.  Add type casts.
diff --git a/src/if_cscope.c b/src/if_cscope.c
index ad29fb9..8094750 100644
--- a/src/if_cscope.c
+++ b/src/if_cscope.c
@@ -961,12 +961,12 @@
 #endif
 	if (csinfo[i].ppath != NULL)
 	{
-	    len = STRLEN(cmd);
+	    len = (int)STRLEN(cmd);
 	    vim_snprintf(cmd + len, cmdlen - len, " -P%s", csinfo[i].ppath);
 	}
 	if (csinfo[i].flags != NULL)
 	{
-	    len = STRLEN(cmd);
+	    len = (int)STRLEN(cmd);
 	    vim_snprintf(cmd + len, cmdlen - len, " %s", csinfo[i].flags);
 	}
 # ifdef UNIX