tgl plls: Disable warnings about unused variable

Looks like this is yet-to-be-implemented code. To be able to build-test
other changes, turn off some warnings about the `PLLs` variable.

TEST=Run this and make sure all builds pass:

 for f in configs/*
 do
     make distclean
     make DEBUG=1 cnf=$f -j$(nproc)
 done

Change-Id: I51a14f7a9d6d6d930b9239ed5d0f61c45f2f123b
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/libgfxinit/+/81852
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: Nico Huber <nico.h@gmx.de>
diff --git a/common/tigerlake/hw-gfx-gma-plls.adb b/common/tigerlake/hw-gfx-gma-plls.adb
index bf58f57..2823870 100644
--- a/common/tigerlake/hw-gfx-gma-plls.adb
+++ b/common/tigerlake/hw-gfx-gma-plls.adb
@@ -27,7 +27,14 @@
    end record;
 
    type PLL_State_Array is array (Configurable_DPLLs) of PLL_State;
+
+   pragma Warnings (Off, "unused variable ""PLLs""",
+                    Reason => "Not yet implemented.");
+   pragma Warnings (Off, "variable ""PLLs"" is assigned but never read",
+                    Reason => "Not yet implemented.");
    PLLs : PLL_State_Array;
+   pragma Warnings (On, "variable ""PLLs"" is assigned but never read");
+   pragma Warnings (On, "unused variable ""PLLs""");
 
    procedure Initialize is
    begin