crosstool-ng: depend on gperf

Fixes http://autobuild.buildroot.net/results/c9b87123709e1010bae19c6bdfd219661efdbdfb

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/crosstool-ng/crosstool-ng.mk

@@ -3,6 +3,6 @@ CROSSTOOL_NG_SOURCE            = crosstool-ng-$(CROSSTOOL_NG_VERSION).tar.bz2
 CROSSTOOL_NG_SITE              = http://crosstool-ng.org/download/crosstool-ng/
 CROSSTOOL_NG_INSTALL_TARGET    = NO
 CROSSTOOL_NG_MAKE              = $(MAKE1)
-HOST_CROSSTOOL_NG_DEPENDENCIES = $(if $(BR2_CCACHE),host-ccache) host-gawk host-automake
+HOST_CROSSTOOL_NG_DEPENDENCIES = $(if $(BR2_CCACHE),host-ccache) host-gawk host-automake host-gperf
 
 $(eval $(call AUTOTARGETS,host))