drm/amd/display: Remove unnecessary variable

drm/amd/display: Remove unnecessary variable

[WHY]
Coverity analysis flagged this code as DEADCODE because
the condition '(!need_recovery)' is never true.

The variable 'need_recovery' is initialized as 'true',
is not assigned to 'false' anywhere before the
conditional statement.

Since the variable is only used for the conditional check,
but the check can never be true, the variable itself is
redundant.

[HOW]
Removed the variable 'need_recovery'.

Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Ivan Lipski <ivlipski@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>