Update code/build to work on Solaris x86
Describe the bug
There hasn't been any build or updates for cmucl on Solaris/x86 for a long time. This is not a primary OS that we support, but we have had builds for it previously.
While working on #97, I did test it on Solaris to verify that the code for the case where SC_EFLAGS was not supported did work. This required a few minor tweaks to get it to run:
uint8_t, and remove an
So, might as well update the code.