riscv: Fix fill_callchain return value

riscv: Fix fill_callchain return value

BugLink: https://bugs.launchpad.net/bugs/1971497
commit 2b2b574ac587ec5bd7716a356492a85ab8b0ce9f upstream.

perf_callchain_store return 0 on success, -1 otherwise,
fix fill_callchain to return correct bool value.

Fixes: dbeb90b0c1eb ("riscv: Add perf callchain support")
Signed-off-by: Nikita Shubin <n.shubin@yadro.com>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>