Revert "msm: ipa4: add support for 6 PDNs"

This reverts commit ce00308aa1f104f4ed6573048d6e44552662d998.
Revert commit because it will cause tethering/hotspot client cannot
connect to IPV4 webside.

Bug: 157902559
Test: Tethering and hotspot test
Change-Id: I1716b09973146a94446758713e510e87bcafb229
Signed-off-by: Mars Lin <marslin@google.com>
diff --git a/drivers/platform/msm/ipa/ipa_v3/ipa_utils.c b/drivers/platform/msm/ipa/ipa_v3/ipa_utils.c
index ffdca69..7c8bda4 100644
--- a/drivers/platform/msm/ipa/ipa_v3/ipa_utils.c
+++ b/drivers/platform/msm/ipa/ipa_v3/ipa_utils.c
@@ -3429,8 +3429,8 @@
 	.uc_descriptor_ram_ofst	= 0x3800,
 	.uc_descriptor_ram_size	= 0x1000,
 	.pdn_config_ofst	= 0x4800,
-	.pdn_config_size	= 0x70,
-	.end_ofst		= 0x4870,
+	.pdn_config_size	= 0x50,
+	.end_ofst		= 0x4850,
 };
 
 
diff --git a/include/uapi/linux/msm_ipa.h b/include/uapi/linux/msm_ipa.h
index b2ccea1..14b5aba 100644
--- a/include/uapi/linux/msm_ipa.h
+++ b/include/uapi/linux/msm_ipa.h
@@ -228,7 +228,7 @@
 /**
  * maximal number of NAT PDNs in the PDN config table
  */
-#define IPA_MAX_PDN_NUM 7
+#define IPA_MAX_PDN_NUM 5
 
 /**
  * enum ipa_client_type - names for the various IPA "clients"