ixgbe: handle parameters for tx and rx EITR, no div0
ixgbe: handle parameters for tx and rx EITR, no div0

The driver was doing a divide by zero when adjusting tx-usecs.
This patch removes the divide by zero code and changes the logic slightly
to ignore tx-usecs in the case of shared TxRx vectors.

Cc: Jesse Brandeburg <e6047e445db6578741afb14ef640164ef6b65e4f@intel.com>
Signed-off-by: Shannon Nelson <14bbe8f00ad7c6d888a504d41f5500c00531af99@intel.com>
Signed-off-by: Jeff Kirsher <87e35f5be20bb3e67f4ba6b86f5f6be3085b1b3a@intel.com>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas