Doc: powerpc: Fix typos in Documentation/powerpc

This patch fix some spelling typo found in Documentation/powerpc.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/Documentation/powerpc/cxl.txt b/Documentation/powerpc/cxl.txt
index 2a230d01..205c1b8 100644
--- a/Documentation/powerpc/cxl.txt
+++ b/Documentation/powerpc/cxl.txt
@@ -133,7 +133,7 @@
     The following file operations are supported on both slave and
     master devices.
 
-    A userspace library libcxl is avaliable here:
+    A userspace library libcxl is available here:
 	https://github.com/ibm-capi/libcxl
     This provides a C interface to this kernel API.