build: AOSP/CM14 fixes (API 24/25, mainly BusyBox-less environment)

These changes are needed by any ROM where devices are configured to
use TOOLBOX/TOYBOX instead of BUSYBOX (i.e., TW_USE_TOOLBOX := true).

Change-Id: I68b88cc9fb857f32864556c4b6c9c8e6ee744051
diff --git a/toolbox/Android.mk b/toolbox/Android.mk
index 4c3e433..07e4738 100644
--- a/toolbox/Android.mk
+++ b/toolbox/Android.mk
@@ -50,26 +50,29 @@
             du \
 
         OUR_TOOLS := \
-            df \
             iftop \
             ioctl \
-            ionice \
             log \
-            ls \
-            lsof \
-            mount \
             nandread \
             newfs_msdos \
             ps \
             prlimit \
-            renice \
             sendevent \
             start \
             stop \
             top \
-            uptime \
-            watchprops \
 
+        ifeq ($(shell test $(PLATFORM_SDK_VERSION) -lt 25; echo $$?),0)
+            OUR_TOOLS += \
+                df \
+                ionice \
+                ls \
+                lsof \
+                mount \
+                renice \
+                uptime \
+                watchprops
+        endif
     else
         ifneq (,$(filter $(PLATFORM_SDK_VERSION), 21 22))
             OUR_TOOLS += \
@@ -217,7 +220,7 @@
     LOCAL_WHOLE_STATIC_LIBRARIES := $(patsubst %,libtoolbox_%,$(BSD_TOOLS))
 endif
 
-ifeq ($(shell test $(PLATFORM_SDK_VERSION) -gt 22; echo $$?),0)
+ifneq (,$(filter $(PLATFORM_SDK_VERSION), 23 24))
     # Rule to make getprop and setprop in M trees where toybox normally
     # provides these tools. Toybox does not allow for easy dynamic
     # configuration, so we would have to include the entire toybox binary