tools/ocaml: Default to useful build output

While hiding details of build output looks pretty to some, defaulting to
doing so deviates from the rest of Xen.  Switch the OCAML tools to match
everything else.

Signed-off-by: Elliott Mitchell <ehem+xen@m5p.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>

tools/ocaml/Makefile.rules

@@ -1,17 +1,20 @@
 ifdef V
-  ifeq ("$(origin V)", "command line")
-    BUILD_VERBOSE = $(V)
-  endif
+	ifeq ("$(origin V)", "command line")
+		BUILD_VERBOSE = $(V)
+	endif
+else
+	V := 1
+	BUILD_VERBOSE := 1
 endif
 ifndef BUILD_VERBOSE
-  BUILD_VERBOSE = 0
+	BUILD_VERBOSE := 0
 endif
 ifeq ($(BUILD_VERBOSE),1)
-  E = @true
-  Q =
+	E := @true
+	Q :=
 else
-  E = @echo
-  Q = @
+	E := @echo
+	Q := @
 endif
 
 .NOTPARALLEL: