x86/vdso: Fix lsl operand order

x86/vdso: Fix lsl operand order

In the __getcpu function, lsl is using the wrong target and destination
registers. Luckily, the compiler tends to choose %eax for both variables,
so it has been working so far.

Fixes: a582c540ac1b ("x86/vdso: Use RDPID in preference to LSL when available")
Signed-off-by: Samuel Neves <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Andy Lutomirski <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]