gperf: remove trailing spaces

package/gperf/gperf.mk

@@ -9,12 +9,12 @@ GPERF_SITE = $(BR2_GNU_MIRROR)/gperf
 GPERF_AUTORECONF = NO
 GPERF_INSTALL_STAGING = YES
 GPERF_INSTALL_TARGET = YES
-GPERF_INSTALL_STAGING_OPT = DESTDIR=$(STAGING_DIR) install 
-GPERF_INSTALL_TARGET_OPT = DESTDIR=$(TARGET_DIR) install 
+GPERF_INSTALL_STAGING_OPT = DESTDIR=$(STAGING_DIR) install
+GPERF_INSTALL_TARGET_OPT = DESTDIR=$(TARGET_DIR) install
 
-GPERF_CONF_ENV = 
+GPERF_CONF_ENV =
 
-GPERF_CONF_OPT = 
+GPERF_CONF_OPT =
 
 GPERF_DEPENDENCIES = uclibc