ARC: [plat-eznps] Add missing struct nps_host_reg_aux_dpc

Fixing compilation issue caused by missing struct nps_host_reg_aux_dpc
definition.

Fixes: 3f9cd874dcc87 ("ARC: [plat-eznps] avoid toggling of DPC register")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Ofer Levi <oferle@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/plat-eznps/include/plat/ctop.h

@@ -143,6 +143,15 @@ struct nps_host_reg_gim_p_int_dst {
 };
 
 /* AUX registers definition */
+struct nps_host_reg_aux_dpc {
+	union {
+		struct {
+			u32 ien:1, men:1, hen:1, reserved:29;
+		};
+		u32 value;
+	};
+};
+
 struct nps_host_reg_aux_udmc {
 	union {
 		struct {