softpipe: change vendor name to something more generic.

For consistency with the llvmpipe driver.

Reviewed-by: Roland Scheidegger <sroland@vmware.com>
Reviewed by: Jose Fonseca <jfonseca@vmware.com>

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5483>

src/gallium/drivers/softpipe/sp_screen.c

@@ -51,7 +51,7 @@ DEBUG_GET_ONCE_BOOL_OPTION(use_llvm, "SOFTPIPE_USE_LLVM", FALSE)
 static const char *
 softpipe_get_vendor(struct pipe_screen *screen)
 {
-   return "VMware, Inc.";
+   return "Mesa/X.org";
 }