BUILD: halog: make halog build on solaris

Solaris' "rm" command does not support -v. Also, specify CC=gcc
because "cc" generally is not gcc there.
diff --git a/contrib/halog/Makefile b/contrib/halog/Makefile
index fa3e6bb..c488470 100644
--- a/contrib/halog/Makefile
+++ b/contrib/halog/Makefile
@@ -1,5 +1,7 @@
 EBTREE_DIR = ../../ebtree
 INCLUDE  = -I../../include -I$(EBTREE_DIR)
+
+CC       = gcc
 OPTIMIZE = -O3
 
 OBJS     = halog halog64
@@ -11,4 +13,4 @@
 	$(CC) $(OPTIMIZE) -o $@ $(INCLUDE) $(EBTREE_DIR)/ebtree.c $(EBTREE_DIR)/eb32tree.c $(EBTREE_DIR)/eb64tree.c $(EBTREE_DIR)/ebmbtree.c $(EBTREE_DIR)/ebsttree.c $(EBTREE_DIR)/ebistree.c $(EBTREE_DIR)/ebimtree.c $^
 
 clean:
-	rm -vf $(OBJS)
+	rm -f $(OBJS)