package/lrzsz: drop bogus LRZSZ_BUILD_HOOKS

Commit "4f3f291a3b lrzsz: convert to autotools infrastructure" converted
the package to use autotools infra but added a define that is never
called.

Drop the bogus define.

Signed-off-by: Ricardo Martincoski <ricardo.martincoski@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/lrzsz/lrzsz.mk

@@ -18,10 +18,6 @@ define LRZSZ_POST_CONFIGURE_HOOKS
 	$(SED) "s~\(#define ENABLE_SYSLOG.*\)~/* \1 */~;" $(@D)/config.h
 endef
 
-define LRZSZ_BUILD_HOOKS
-	$(TARGET_MAKE_ENV) $(MAKE) CROSS_COMPILE="$(TARGET_CROSS)" prefix="$(TARGET_DIR)" -C $(@D)
-endef
-
 define LRZSZ_INSTALL_TARGET_CMDS
 	$(INSTALL) -m 0755 -D $(@D)/src/lrz $(TARGET_DIR)/usr/bin/rz
 	$(INSTALL) -m 0755 -D $(@D)/src/lsz $(TARGET_DIR)/usr/bin/sz