net/mlx4: compact interrupt functions

net/mlx4: compact interrupt functions

Link status (LSC) and removal (RMV) interrupts share a common handler and
are toggled simultaneously from common install/uninstall functions.

Four additional wrapper functions (two for each interrupt type) are
currently necessary because the PMD maintains an internal configuration
state for interrupts (priv->intr_conf).

This complexity can be avoided entirely since the PMD does not disable
interrupts configuration parameters in case of error anymore.

With this commit, only two functions are necessary to toggle interrupts
(including Rx) during start/stop cycles.

Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>