cpu_x86_find_by_name() uses strtosz_suffix_unit(), but screws up the
error checking. It detects some failures, but not all. Undetected
failures result in a zero tsc_khz value (error value -1 divided by
1000), which means "no tsc_freq set".
To reproduce, try "-cpu qemu64,tsc_freq=9999999T".
strtosz_suffix_unit() fails, because the value overflows int64_t,
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>