Add scalbln, scalblnf, and scalblnl to x86 libm.so for API>=18

Change-Id: Ib22eead27b8f82cfa0e1b7eb429e2c76d068120f
diff --git a/ndk/platforms/android-18/arch-x86/symbols/libm.so.functions.txt b/ndk/platforms/android-18/arch-x86/symbols/libm.so.functions.txt
index e78f0e3..25ba19e 100644
--- a/ndk/platforms/android-18/arch-x86/symbols/libm.so.functions.txt
+++ b/ndk/platforms/android-18/arch-x86/symbols/libm.so.functions.txt
@@ -171,6 +171,9 @@
 roundl
 scalb
 scalbf
+scalbln
+scalblnf
+scalblnl
 scalbn
 scalbnf
 scalbnl