Disable LTO bootstrap (experiment)

This should significantly improve build time.

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

gcc.spec

@@ -141,7 +141,7 @@
 Summary: Various compilers (C, C++, Objective-C, ...)
 Name: gcc
 Version: %{gcc_version}
-Release: %{gcc_release}.15%{?dist}
+Release: %{gcc_release}.15.0.riscv64%{?dist}
 # License notes for some of the less obvious ones:
 #   gcc/doc/cppinternals.texi: Linux-man-pages-copyleft-2-para
 #   isl: MIT, BSD-2-Clause
@@ -1263,7 +1263,7 @@ CONFIGURE_OPTS="\
 	--build=%{gcc_target_platform} \
 %endif
 %if 0%{?fedora} >= 35 || 0%{?rhel} >= 9
-%ifnarch %{arm}
+%ifnarch %{arm} riscv64
 	--with-build-config=bootstrap-lto --enable-link-serialization=1 \
 %endif
 %endif
@@ -3621,6 +3621,9 @@ end
 %endif
 
 %changelog
+* Tue Apr 16 2024 David Abdurachamnov <davidlt@rivosinc.com> 14.0.1-0.15.0.riscv64
+- Disable LTO bootstrap (experiment)
+
 * Thu Apr 11 2024 Jakub Jelinek <jakub@redhat.com> 14.0.1-0.15
 - update from trunk
   - PRs analyzer/114472, c++/114303, c++/114409, debug/112878,