Fix typos in external/libtommath/README
The LibTom Projects website is not "http://www.libtom.org/"
but "https://www.libtom.net/"
Change-Id: I2334242aef7ed82de94e8814a8102d2ef970745a
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/153781
Tested-by: Julien Nabet <serval2412@yahoo.fr>
Reviewed-by: Julien Nabet <serval2412@yahoo.fr>
(cherry picked from commit
d1ee7e816cc8f4edd146a035cd37ef848738bc21)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/153760
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolan.mcnamara@collabora.com>