qcacld-3.0: Enable compilation for new dp_rings_main.c file

Add support to compile new dp_rings_main.c file.
This new file is having refactored code of all the DP rings.

Change-Id: I7cd467df8d3f7c4b60d448c88b5cedc76cd62b07
CRs-Fixed: 3423636

Kbuild

@@ -2171,6 +2171,7 @@ DP_INC := -I$(WLAN_COMMON_INC)/dp/inc \
 
 DP_SRC := $(WLAN_COMMON_ROOT)/dp/wifi3.0
 DP_OBJS := $(DP_SRC)/dp_main.o \
+		$(DP_SRC)/dp_rings_main.o \
 		$(DP_SRC)/dp_tx.o \
 		$(DP_SRC)/dp_arch_ops.o \
 		$(DP_SRC)/dp_tx_desc.o \