ARC: [plat-eznps] disabled stall counter due to a HW bug

This counter represents threshold for consecutive stall which
would trigger HW threads scheduling. However when enabled, low
threshhold values cause performance degradation and in the
worst case even livelock.

So disable it by resorting to HW reset value
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Reviewed-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: fixed changelog]

arch/arc/plat-eznps/mtm.c

@@ -119,8 +119,6 @@ void mtm_enable_core(unsigned int cpu)
 	mt_ctrl.value = 0;
 	mt_ctrl.hsen = 1;
 	mt_ctrl.hs_cnt = MT_CTRL_HS_CNT;
-	mt_ctrl.sten = 1;
-	mt_ctrl.st_cnt = MT_CTRL_ST_CNT;
 	mt_ctrl.mten = 1;
 	write_aux_reg(CTOP_AUX_MT_CTRL, mt_ctrl.value);