net: ipa: support more than 6 resource groups

IPA versions 3.0 and 3.1 support up to 8 resource groups.  There is
some interest in supporting these older versions of the hardware, so
update the resource configuration code to program resource limits
for these groups if specified.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>