POSIX arch: Fix literal floating comparison in 32bit targets

When building the 32bit native board targets variants
for x86(-64) hosts, gcc will promote float literals to double
(See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92875 )

This can result in unexpected comparison differences.

This is due to the compiler using the 8087 float mode by
default.
Instead let's tell the compiler to use the SSE float path,
which is the default for 64 bit x86-64 builds.

The assumption that any x86 host used for development
will have SSE support should be safe enough.

For more background see
https://github.com/zephyrproject-rtos/zephyr/issues/61345



Signed-off-by: Alberto Escolar Piedras <alberto.escolar.piedras@nordicsemi.no>
(cherry picked from commit d4e48d5f)