Makefile: fix db-specific ldflags (#7554)

Closes: #7534

Author: Alessio Treglia

Makefile

@@ -70,10 +70,12 @@ endif
 ifeq (rocksdb,$(findstring rocksdb,$(COSMOS_BUILD_OPTIONS)))
   CGO_ENABLED=1
   BUILD_TAGS += rocksdb
+  ldflags += -X github.com/cosmos/cosmos-sdk/types.DBBackend=rocksdb
 endif
 # handle boltdb
 ifeq (boltdb,$(findstring boltdb,$(COSMOS_BUILD_OPTIONS)))
   BUILD_TAGS += boltdb
+  ldflags += -X github.com/cosmos/cosmos-sdk/types.DBBackend=boltdb
 endif
 
 ifeq (,$(findstring nostrip,$(COSMOS_BUILD_OPTIONS)))