ALSA: hda - Update model descriptions in patch_sigmatel.c

Update models in patch_sigmatel.c, mainly for the last Gateway updates.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Documentation/sound/alsa/HD-Audio-Models.txt

@@ -275,7 +275,8 @@ STAC9200
   dell-m25	Dell Inspiron E1505n
   dell-m26	Dell Inspiron 1501
   dell-m27	Dell Inspiron E1705/9400
-  gateway	Gateway laptops with EAPD control
+  gateway-m4	Gateway laptops with EAPD control
+  gateway-m4-2	Gateway laptops with EAPD control
   panasonic	Panasonic CF-74
 
 STAC9205/9254
@@ -302,6 +303,7 @@ STAC9220/9221
   macbook-pro	Intel Mac Book Pro 2nd generation (eq. type 3)
   imac-intel	Intel iMac (eq. type 2)
   imac-intel-20	Intel iMac (newer version) (eq. type 3)
+  ecs202	ECS/PC chips
   dell-d81	Dell (unknown)
   dell-d82	Dell (unknown)
   dell-m81	Dell (unknown)
@@ -310,9 +312,13 @@ STAC9220/9221
 STAC9202/9250/9251
 ==================
   ref		Reference board, base config
+  m1		Some Gateway MX series laptops (NX560XL)
+  m1-2		Some Gateway MX series laptops (MX6453)
+  m2		Some Gateway MX series laptops (M255)
   m2-2		Some Gateway MX series laptops
+  m3		Some Gateway MX series laptops
+  m5		Some Gateway MX series laptops (MP6954)
   m6		Some Gateway NX series laptops
-  pa6		Gateway NX860 series
 
 STAC9227/9228/9229/927x
 =======================
@@ -329,6 +335,7 @@ STAC92HD71B*
   dell-m4-1	Dell desktops
   dell-m4-2	Dell desktops
   dell-m4-3	Dell desktops
+  hp-m4		HP dv laptops
 
 STAC92HD73*
 ===========
@@ -337,6 +344,7 @@ STAC92HD73*
   dell-m6-amic	Dell desktops/laptops with analog mics
   dell-m6-dmic	Dell desktops/laptops with digital mics
   dell-m6	Dell desktops/laptops with both type of mics
+  dell-eq	Dell desktops/laptops
 
 STAC92HD83*
 ===========