PEL: Removed unused include in ascii_string.cpp

The class doesn't write anything to the journal so remove the
phosphor-logging/log.hpp include.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I25ffeaa8e581d1e6667c8ede9c6a345bd76ce78c
diff --git a/extensions/openpower-pels/ascii_string.cpp b/extensions/openpower-pels/ascii_string.cpp
index 7e0f493..54f3837 100644
--- a/extensions/openpower-pels/ascii_string.cpp
+++ b/extensions/openpower-pels/ascii_string.cpp
@@ -17,8 +17,6 @@
 
 #include "pel_types.hpp"
 
-#include <phosphor-logging/log.hpp>
-
 namespace openpower
 {
 namespace pels
@@ -26,8 +24,6 @@
 namespace src
 {
 
-using namespace phosphor::logging;
-
 AsciiString::AsciiString(Stream& stream)
 {
     unflatten(stream);