x86/early-quirks: replace the magical increment start values

Replace the magical +2, +9 etc. with +MB, which is far easier to read.
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171211151822.20953-4-matthew.auld@intel.com

arch/x86/kernel/early-quirks.c

@@ -428,9 +428,9 @@ static resource_size_t __init chv_stolen_size(int num, int slot, int func)
 	if (gms < 0x11)
 		return gms * MB(32);
 	else if (gms < 0x17)
-		return (gms - 0x11 + 2) * MB(4);
+		return (gms - 0x11) * MB(4) + MB(8);
 	else
-		return (gms - 0x17 + 9) * MB(4);
+		return (gms - 0x17) * MB(4) + MB(36);
 }
 
 static resource_size_t __init gen9_stolen_size(int num, int slot, int func)
@@ -446,7 +446,7 @@ static resource_size_t __init gen9_stolen_size(int num, int slot, int func)
 	if (gms < 0xf0)
 		return gms * MB(32);
 	else
-		return (gms - 0xf0 + 1) * MB(4);
+		return (gms - 0xf0) * MB(4) + MB(4);
 }
 
 struct intel_early_ops {