Skip panic_abort_doc_tests on riscv64

riscv64 is also affected by:
https://github.com/rust-lang/rust/issues/123733

Signed-off-by: David Abdurachmanov <davidlt@rivosinc.com>

rust.spec

@@ -1,6 +1,6 @@
 Name:           rust
 Version:        1.78.0
-Release:        %autorelease -e 0.riscv64
+Release:        %autorelease -e 1.riscv64
 Summary:        The Rust Programming Language
 License:        (Apache-2.0 OR MIT) AND (Artistic-2.0 AND BSD-3-Clause AND ISC AND MIT AND MPL-2.0 AND Unicode-DFS-2016)
 # ^ written as: (rust itself) and (bundled libraries)
@@ -973,9 +973,6 @@ rm -f %{buildroot}%{rustlibdir}/%{rust_triple}/bin/rust-ll*
 
 
 %check
-# Hack to avoid leaky test consuming all memory (riscv64).
-exit 0
-
 %if 0%{?rhel} && 0%{?rhel} <= 9
 %{?set_build_flags}
 %endif
@@ -1009,7 +1006,7 @@ rm -rf "$TMP_HELLO"
 %{__x} test --no-fail-fast --skip src/bootstrap || :
 rm -rf "./build/%{rust_triple}/test/"
 
-%ifarch aarch64
+%ifarch aarch64 riscv64
 # https://github.com/rust-lang/rust/issues/123733
 %define cargo_test_skip --test-args "--skip panic_abort_doc_tests"
 %endif