gma broxton: Tighten types to rely less on proof inlining

Change-Id: I2ff61484715461026463be7fbc45c283e75c903b
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: https://review.coreboot.org/26842
Tested-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/common/broxton/hw-gfx-gma-plls.adb b/common/broxton/hw-gfx-gma-plls.adb
index 7da47f2..087ff12 100644
--- a/common/broxton/hw-gfx-gma-plls.adb
+++ b/common/broxton/hw-gfx-gma-plls.adb
@@ -330,7 +330,7 @@
 
    ----------------------------------------------------------------------------
 
-   procedure Program_DPLL (P : T; Clock : Clock_Type)
+   procedure Program_DPLL (P : Valid_PLLs; Clock : Clock_Type)
    is
       PCS : Word32;
    begin