This reverts commit cc2bc0bf.  As discussed at
<https://gerrit.libreoffice.org/#/c/55783/> "Fix nan is not a member of std when
building android":

Stephan: "with exactly what architecture and toolchain did that failure happen;
is this commit still relevant after <https://gerrit.libreoffice.org/plugins/
gitiles/core/+/312eeeee%5E!/> 'Switch Android
armeabi-v7a to libc++/libc++abi/libunwind too'?"

Tomaž: "It was a consequence of that limited Bionic libstdc++ that was used in
ANdorid. libc++ should be a modern up-to-date replacements so I guess this
workaraunds are now obsolete and irrelevant."

(And a --with-distro=LibreOfficeAndroid build against NDK r16b indeed succeeded
for me with this revert.)

Conflicts:
	external/libwps/UnpackedTarball_libwps.mk

Change-Id: I2dba64e5712b20fa07f6374ae01c226025c52d8b
Reviewed-on: https://gerrit.libreoffice.org/66390
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>