package/tpm2-tss: fix build without C++

package/tpm2-tss: fix build without C++

C++ is required only for the fuzzing tests but AC_PROG_CXX is included
by configure.ac even when fuzzing is not enabled (which we don't do on
Buildroot).

The patch applied upstream had issues and was reverted[1]. Use a local
patch to solve the problem temporaryly.

Fixes:
    http://autobuild.buildroot.net/results/13f5e37b47b255da4158bec34e5459136f7e60d4
    http://autobuild.buildroot.net/results/1c26db2509c79e00c0de1165945277eaa57b149f
    http://autobuild.buildroot.net/results/b7b6b7b7aca79e847b442cbd2305427d91fe5d70
    http://autobuild.buildroot.net/results/1cd5a82a0e799aa5027e2e2c03b246332cc3a15d
    http://autobuild.buildroot.net/results/d7ec878907f714377c83e9a496e97cbf9382d787
    http://autobuild.buildroot.net/results/1c7f0c1b3ce4871cd87bd6059b1f0a6dc4e74a9c
    http://autobuild.buildroot.net/results/196b81d580325607c8da90beeb79e1f6b8ab8b47
    http://autobuild.buildroot.net/results/f90f7b4ac710b56686635f8ae27059c11b963e47

1. https://github.com/tpm2-software/tpm2-tss/commit/60c26e4c4faba6ba12469485653e17092b510840

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>