fix spelling in main directory

Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
diff --git a/cpu-all.h b/cpu-all.h
index 5f47ab8..7246a67 100644
--- a/cpu-all.h
+++ b/cpu-all.h
@@ -368,7 +368,7 @@
 #define CPU_INTERRUPT_TGT_EXT_4   0x1000
 
 /* Several target-specific internal interrupts.  These differ from the
-   preceeding target-specific interrupts in that they are intended to
+   preceding target-specific interrupts in that they are intended to
    originate from within the cpu itself, typically in response to some
    instruction being executed.  These, therefore, are not masked while
    single-stepping within the debugger.  */