tools: iio: Add iio targets in tools Makefile

This patch adds targets for building and cleaning iio tools to tools/Makefile.
To build iio tools from the toplevel kernel directory one should call:

$ make -C tools iio

and for cleaning it

$ make -C tools iio_clean
Signed-off-by: Roberta Dobrescu <roberta.dobrescu@gmail.com>
Reviewed-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

tools/Makefile

@@ -8,6 +8,7 @@ help:
 	@echo '  cpupower   - a tool for all things x86 CPU power'
 	@echo '  firewire   - the userspace part of nosy, an IEEE-1394 traffic sniffer'
 	@echo '  hv         - tools used when in Hyper-V clients'
+	@echo '  iio        - IIO tools'
 	@echo '  lguest     - a minimal 32-bit x86 hypervisor'
 	@echo '  perf       - Linux performance measurement and analysis tool'
 	@echo '  selftests  - various kernel selftests'
@@ -41,7 +42,7 @@ acpi: FORCE
 cpupower: FORCE
 	$(call descend,power/$@)
 
-cgroup firewire hv guest usb virtio vm net: FORCE
+cgroup firewire hv guest usb virtio vm net iio: FORCE
 	$(call descend,$@)
 
 liblockdep: FORCE
@@ -91,7 +92,7 @@ acpi_clean:
 cpupower_clean:
 	$(call descend,power/cpupower,clean)
 
-cgroup_clean hv_clean firewire_clean lguest_clean usb_clean virtio_clean vm_clean net_clean:
+cgroup_clean hv_clean firewire_clean lguest_clean usb_clean virtio_clean vm_clean net_clean iio_clean:
 	$(call descend,$(@:_clean=),clean)
 
 liblockdep_clean:
@@ -114,6 +115,6 @@ tmon_clean:
 
 clean: acpi_clean cgroup_clean cpupower_clean hv_clean firewire_clean lguest_clean \
 		perf_clean selftests_clean turbostat_clean usb_clean virtio_clean \
-		vm_clean net_clean x86_energy_perf_policy_clean tmon_clean
+		vm_clean net_clean iio_clean x86_energy_perf_policy_clean tmon_clean
 
 .PHONY: FORCE