Fixed check for copy_file_range on Android

    AC_CHECK_FUNCS apparently doesn't take into account the __ANDROID_API__ level properly and so incorrectly determines that copy_file_range is available for termux at API 24 but copy_file_range is <= 34.

    Ticket: none
    Changelog: none

Author: craigcomstock

configure.ac

@@ -895,7 +895,7 @@ AC_CHECK_DECLS([FALLOC_FL_PUNCH_HOLE], [], [], [
 ])
 AC_CHECK_HEADERS([sys/sendfile.h])
 AC_CHECK_FUNCS([sendfile])
-AC_CHECK_FUNCS([copy_file_range])
+AC_CHECK_DECL([copy_file_range])
 
 
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