drm/i915: replace IS_GEN<N> with IS_GEN(..., N)

Define IS_GEN() similarly to our IS_GEN_RANGE(). but use gen instead of
gen_mask to do the comparison. Now callers can pass then gen as a parameter,
so we don't require one macro for each gen.

The following spatch was used to convert the users of these macros:

@@
expression e;
@@
(
- IS_GEN2(e)
+ IS_GEN(e, 2)
|
- IS_GEN3(e)
+ IS_GEN(e, 3)
|
- IS_GEN4(e)
+ IS_GEN(e, 4)
|
- IS_GEN5(e)
+ IS_GEN(e, 5)
|
- IS_GEN6(e)
+ IS_GEN(e, 6)
|
- IS_GEN7(e)
+ IS_GEN(e, 7)
|
- IS_GEN8(e)
+ IS_GEN(e, 8)
|
- IS_GEN9(e)
+ IS_GEN(e, 9)
|
- IS_GEN10(e)
+ IS_GEN(e, 10)
|
- IS_GEN11(e)
+ IS_GEN(e, 11)
)

v2: use IS_GEN rather than GT_GEN and compare to info.gen rather than
    using the bitmask

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181212181044.15886-2-lucas.demarchi@intel.com

drivers/gpu/drm/i915/intel_psr.c

@@ -552,7 +552,7 @@ static bool intel_psr2_config_valid(struct intel_dp *intel_dp,
 	if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)) {
 		psr_max_h = 4096;
 		psr_max_v = 2304;
-	} else if (IS_GEN9(dev_priv)) {
+	} else if (IS_GEN(dev_priv, 9)) {
 		psr_max_h = 3640;
 		psr_max_v = 2304;
 	}
@@ -686,7 +686,7 @@ static void intel_psr_enable_source(struct intel_dp *intel_dp,
 	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
 		hsw_psr_setup_aux(intel_dp);
 
-	if (dev_priv->psr.psr2_enabled && (IS_GEN9(dev_priv) &&
+	if (dev_priv->psr.psr2_enabled && (IS_GEN(dev_priv, 9) &&
 					   !IS_GEMINILAKE(dev_priv))) {
 		i915_reg_t reg = gen9_chicken_trans_reg(dev_priv,
 							cpu_transcoder);