Fix max bmc dump size test

Changes:
    - Added variable to allow user driven number of dumps to create.
    
Tested:
    Ran successfully , example bellow
    robot -v OPENBMC_HOST:xxx.xx.xx.xx -v BMC_MAX_DUMP_COUNT:1000
          -v BMC_DUMP_TOTAL_SIZE:409600
          --include Verify_Maximum_BMC_Dump_Creation
          redfish/managers/test_bmc_dumps.robot 


Change-Id: I989dc6dc4fa12530fbb2b95e6d17e198632586c1
Signed-off-by: manashsarma <manashsarma@in.ibm.com>
diff --git a/redfish/managers/test_bmc_dumps.robot b/redfish/managers/test_bmc_dumps.robot
index 6ab0930..1d7a4e5 100644
--- a/redfish/managers/test_bmc_dumps.robot
+++ b/redfish/managers/test_bmc_dumps.robot
@@ -18,6 +18,7 @@
 
 # Minimum space required for one bmc dump in kilo bytes
 ${BMC_DUMP_MIN_SPACE_REQD}   ${20}
+${MAX_DUMP_COUNT}            ${20}
 
 *** Test Cases ***
 
@@ -165,8 +166,8 @@
     # Maximum allowed space for dump is 1024 KB. BMC typically hold 8-14 dumps
     # before running out of this dump space. So trying to create dumps in 20
     # iterations to run out of space.
-
-    FOR  ${n}  IN RANGE  0  20
+    # User can key in the Maximum allowed space for bmc dump and how many iteration.
+    FOR  ${n}  IN RANGE  0  ${MAX_DUMP_COUNT}
       Create User Initiated BMC Dump Via Redfish
       ${dump_space}=  Get Disk Usage For Dumps
       Exit For Loop If  ${dump_space} >= (${BMC_DUMP_TOTAL_SIZE} - ${BMC_DUMP_MIN_SPACE_REQD})