C++: Delete empty source file

Change-Id: Ib86e09d6d516b175e715725fa9b60d7ae2626ff8
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/libs/3rdparty/cplusplus/ASTPatternBuilder.cpp

-
-#include "ASTPatternBuilder.h"

src/libs/3rdparty/cplusplus/cplusplus.pri

@@ -40,7 +40,6 @@ SOURCES += \
     $$PWD/ASTMatch0.cpp \
     $$PWD/ASTVisitor.cpp \
     $$PWD/ASTClone.cpp \
-    $$PWD/ASTPatternBuilder.cpp \
     $$PWD/ASTMatcher.cpp \
     $$PWD/Matcher.cpp \
     $$PWD/Control.cpp \

src/libs/cplusplus/cplusplus.qbs

@@ -30,7 +30,6 @@ Project {
                 "ASTMatch0.cpp",
                 "ASTMatcher.cpp",
                 "ASTMatcher.h",
-                "ASTPatternBuilder.cpp",
                 "ASTPatternBuilder.h",
                 "ASTVisit.cpp",
                 "ASTVisitor.cpp",