parisc/Kconfig: SMP kernels boot on all machines

I'm not aware of any machines which won't be able to run our SMP kernel.
Refine the Kconfig help text.

Signed-off-by: Helge Deller <deller@gmx.de>

arch/parisc/Kconfig

@@ -276,10 +276,8 @@ config SMP
 	  than one CPU, say Y.
 
 	  If you say N here, the kernel will run on uni- and multiprocessor
-	  machines, but will use only one CPU of a multiprocessor machine. If
+	  machines, but will use only one CPU of a multiprocessor machine.
-	  you say Y here, the kernel will run on many, but not all,
+	  On a uniprocessor machine, the kernel will run faster if you say N.
-	  uniprocessor machines. On a uniprocessor machine, the kernel
-	  will run faster if you say N here.
 
 	  See also <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO
 	  available at <http://www.tldp.org/docs.html#howto>.