Fix gcc format warning in snprintf
Fix gcc format warning in snprintf

gcc 8 produces the following warnings:

server/I2CInstruction.C: In member function ‘virtual uint32_t I2CInstruction::execute(ecmdDataBuffer&, InstructionStatus&, Handle**)’:
server/I2CInstruction.C:288:35: warning: format ‘%zu’ expects argument of type ‘size_t’, but argument 5 has type ‘int’ [-Wformat=]
             snprintf(errstr, 200, "SERVER_DEBUG : iic_reset() SERVER_I2CRESETLIGHT errno=%d, rc = %zu)\n", errno, rcReset);
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~         ~~~~~~~
server/I2CInstruction.C:325:35: warning: format ‘%zu’ expects argument of type ‘size_t’, but argument 5 has type ‘int’ [-Wformat=]
             snprintf(errstr, 200, "SERVER_DEBUG : iic_reset() SERVER_I2CRESETFULL errno=%d, rc = %zu)\n", errno, rcReset);
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~         ~~~~~~~

Use the proper format string for the int type of rcReset. Use %d
rather than %i to match the convention used elsewhere in the file.

Signed-off-by: Ryan King <b0f757ae34e4d5e08341e0046ecf2ce9ace939d9@us.ibm.com>

open-power/eCMD,open-power/eCMD,open-power/eCMD,open-power/eCMD,open-power/eCMD