drivers/tty/hvc: don't free hvc_console_setup after init

When 'console=hvc0' is specified to the kernel parameter in x86 KVM guest,
hvc console is setup within a kthread. However, that will cause SEGV
and the boot will fail when the driver is builtin to the kernel,
because currently hvc_console_setup() is annotated with '__init'. This
patch removes '__init' to boot the guest successfully with 'console=hvc0'.

Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@hds.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>