Import a very trimmed-down set of libtasn1 files:
pushd /tmp
wget https://ftp.gnu.org/gnu/libtasn1/libtasn1-4.16.0.tar.gz
popd
pushd grub-core/lib
mkdir libtasn1
cp /tmp/libtasn1-4.16.0/{README.md,LICENSE} libtasn1/
mkdir libtasn1/lib
cp
/tmp/libtasn1-4.16.0/lib/{coding.c,decoding.c,element.c,element.h,errors.c,gstr.c,gstr.h,int.h,parser_aux.c,parser_aux.h,structure.c,structure.h}
libtasn1/lib
cp /tmp/libtasn1-4.16.0/lib/includes/libtasn1.h ../../include/grub/
git add libtasn1/ ../../include/grub/libtasn1.h
popd
Signed-off-by: Daniel Axtens <dja@axtens.net>