Update oc_i2c_master_hw.tcl

On Quartus 13.1 the generation of the nios_system.v file from a variable type of STD_LOGIC will result in a verilog line of:
	i2c_master_top #(
		.ARST_LVL ('1')
	) oc_i2c_master_0 (
which will stop the build of the bitstream. Changing the interface property of the ARST_LVL parameter to integer would solve thie issue.
Change:
add_parameter ARST_LVL STD_LOGIC 0 ""
...
set_parameter_property ARST_LVL TYPE STD_LOGIC
To
add_parameter ARST_LVL STD_LOGIC 0 ""
...
set_parameter_property ARST_LVL TYPE INTEGER