Modified the test file to fix Invalid IP prefix format error while creatimg route entry (#1959)

Modified the test file to fix Invalid IP prefix format error while Creating route entry. Please find error details given below

Finish SaiHelperBase setup
Create default v4&v6 route entry...
Create neighbor with 172.16.10.1 ip address, 1688849860263944 router interface id and 00:11:22:33:44:55 destination mac
Create nhop with 172.16.10.1 ip address and 1688849860263944 router interface id
Create route with 172.16.10.0 ip prefix and 1688849860263944 router interface id
Invalid IP prefix format

Added prefix with sbunet to fix this issue

Author: rajneeshaec

ptf/saiacl.py

@@ -558,7 +558,7 @@ def setUp(self):
         rif_id1 = self.port0_rif
         self.rif_id2 = self.port1_rif
 
-        ip_addr_subnet = '172.16.10.0'
+        ip_addr_subnet = '172.16.10.0/24'
         ip_addr = '172.16.10.1'
         dmac = '00:11:22:33:44:55'
         mac_src = '00:22:22:22:22:22'
@@ -815,7 +815,7 @@ def setUp(self):
         rif_id1 = self.port0_rif
         self.rif_id2 = self.port1_rif
 
-        ip_addr_subnet = '172.16.10.0'
+        ip_addr_subnet = '172.16.10.0/24'
         ip_addr = '172.16.10.1'
         dmac = '00:11:22:33:44:55'
         mac_src = '00:22:22:22:22:22'
@@ -1071,7 +1071,7 @@ def setUp(self):
         rif_id1 = self.port0_rif
         self.rif_id2 = self.port1_rif
 
-        ip_addr_subnet = '172.16.10.0'
+        ip_addr_subnet = '172.16.10.0/24'
         ip_addr = '172.16.10.1'
         dmac = '00:11:22:33:44:55'
         self.mac_src = '00:22:22:22:22:22'
@@ -1331,7 +1331,7 @@ def setUp(self):
         rif_id1 = self.port0_rif
         self.rif_id2 = self.port1_rif
 
-        ip_addr_subnet = '172.16.10.0'
+        ip_addr_subnet = '172.16.10.0/24'
         ip_addr = '172.16.10.1'
         dmac = '00:11:22:33:44:55'
         mac_src = '00:22:22:22:22:22'
@@ -1611,7 +1611,7 @@ def setUp(self):
         rif_id1 = self.port0_rif
         self.rif_id2 = self.port1_rif
 
-        ip_addr_subnet = '172.16.10.0'
+        ip_addr_subnet = '172.16.10.0/24'
         ip_addr = '172.16.10.1'
         dmac = '00:11:22:33:44:55'
         mac_src = '00:22:22:22:22:22'
@@ -2547,7 +2547,7 @@ def setUp(self):
         super(MultAclTableGroupBindTest, self).setUp()
         rif_id = self.port13_rif
 
-        ip_addr_subnet = '172.16.10.0'
+        ip_addr_subnet = '172.16.10.0/24'
         self.ip_addr = '172.16.10.1'
         self.dmac = '00:11:22:33:44:55'