Do not define __USE_FILE_OFFSET64 as it causes fsetpos&fgetpos to be
undefined on api levels lower than android-24.

diff -u -r ../boost_1_64_0/libs/filesystem/src/operations.cpp ./libs/filesystem/src/operations.cpp
--- ../boost_1_64_0/libs/filesystem/src/operations.cpp	2017-04-17 04:22:19.000000000 +0200
+++ ./libs/filesystem/src/operations.cpp	2017-08-08 10:08:13.607302273 +0200
@@ -15,6 +15,7 @@
 #define _FILE_OFFSET_BITS 64 // at worst, these defines may have no effect,
 #endif
 #if !defined(__PGI)
+#if !defined(__ANDROID__)
 #define __USE_FILE_OFFSET64 // but that is harmless on Windows and on POSIX
       // 64-bit systems or on 32-bit systems which don't have files larger 
       // than can be represented by a traditional POSIX/UNIX off_t type. 
@@ -25,6 +26,7 @@
       // ensure that they are available to all included headers.
       // That is required at least on Solaris, and possibly on other
       // systems as well.
+#endif
 #else
 #define _FILE_OFFSET_BITS 64
 #endif