drm/i915: Invert if/else ladder for stolen init

Continue converting the driver to the convention of last version first,
extending it to the future platforms. Now, any GRAPHICS_VER >= 11 will
be handled by the first branch.
Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220908-if-ladder-v2-3-7a7b15545c93@intel.com
Link: https://patchwork.freedesktop.org/patch/msgid/20220912-copy-engine-v1-1-ef92fd81758d@intel.com

drivers/gpu/drm/i915/gem/i915_gem_stolen.c

@@ -428,48 +428,29 @@ static int i915_gem_init_stolen(struct intel_memory_region *mem)
 	reserved_base = stolen_top;
 	reserved_size = 0;
 
-	switch (GRAPHICS_VER(i915)) {
-	case 2:
-	case 3:
-		break;
-	case 4:
-		if (!IS_G4X(i915))
-			break;
-		fallthrough;
-	case 5:
-		g4x_get_stolen_reserved(i915, uncore,
+	if (GRAPHICS_VER(i915) >= 11) {
+		icl_get_stolen_reserved(i915, uncore,
 					&reserved_base, &reserved_size);
-		break;
-	case 6:
-		gen6_get_stolen_reserved(i915, uncore,
-					 &reserved_base, &reserved_size);
-		break;
-	case 7:
-		if (IS_VALLEYVIEW(i915))
-			vlv_get_stolen_reserved(i915, uncore,
-						&reserved_base, &reserved_size);
-		else
-			gen7_get_stolen_reserved(i915, uncore,
-						 &reserved_base, &reserved_size);
-		break;
-	case 8:
-	case 9:
+	} else if (GRAPHICS_VER(i915) >= 8) {
 		if (IS_LP(i915))
 			chv_get_stolen_reserved(i915, uncore,
 						&reserved_base, &reserved_size);
 		else
 			bdw_get_stolen_reserved(i915, uncore,
 						&reserved_base, &reserved_size);
-		break;
-	default:
-		MISSING_CASE(GRAPHICS_VER(i915));
-		fallthrough;
-	case 11:
-	case 12:
-		icl_get_stolen_reserved(i915, uncore,
-					&reserved_base,
-					&reserved_size);
-		break;
+	} else if (GRAPHICS_VER(i915) >= 7) {
+		if (IS_VALLEYVIEW(i915))
+			vlv_get_stolen_reserved(i915, uncore,
+						&reserved_base, &reserved_size);
+		else
+			gen7_get_stolen_reserved(i915, uncore,
+						 &reserved_base, &reserved_size);
+	} else if (GRAPHICS_VER(i915) >= 6) {
+		gen6_get_stolen_reserved(i915, uncore,
+					 &reserved_base, &reserved_size);
+	} else if (GRAPHICS_VER(i915) >= 5 || IS_G4X(i915)) {
+		g4x_get_stolen_reserved(i915, uncore,
+					&reserved_base, &reserved_size);
 	}
 
 	/*