openssl: Fix build on risc64/musl

openssl: Fix build on risc64/musl

__NR_riscv_hwprobe is not exported in musl's hwprobe.h
this fails to build with newer kernels

Fixes
| :85:20: error: use of undeclared identifier '__NR_riscv_hwprobe'; did you mean 'riscv_hwprobe'?
|    85 |     return syscall(__NR_riscv_hwprobe, pairs, pair_count, cpu_count, cpus, flags);
|       |                    ^~~~~~~~~~~~~~~~~~

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>