be2net: Avoid accessing eq object in be_msix_register routine, when i < 0.

When the first request_irq fails in be_msix_register, i value
would be zero. The current code decrements the i value and
accesses the eq object without validating the decremented
"i" value. This can cause an "invalid memory address access"
violation.

This patch fixes the problem by accessing the eq object after
validating the "i" value.

Signed-off-by: Venkat Duvvuru <venkatkumar.duvvuru@avagotech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>