[Bug target/84148] CET shouldn't be enabled in 32-bit run-time libraries by default

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84148

--- Comment #10 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to igor.v.tsimbalist from comment #9)
> How can I check the fixes w/o old HW? I tried specifying --target=pentium to
> configure but the build has failed with the message
> 
> *** Configuration i586-pc-none not supported
> make[1]: *** [configure-gcc] Error 1
> make[1]: Leaving directory `/export/users/itsimbal/gcc_ws/build.cet'
> make: *** [all] Error 2

To specify the default -march= for 32-bit target libraries, for 32-bit
GCC, use --with-arch=cpu, for 64-bit GCC, use --with-arch_32=cpu to
configure GCC.