replace assert.h with cassert

The former was deprecated with C++14.

According to the C++11 and C++17 standards, both files are identical.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

src/tag/ApeLoader.cxx

@@ -22,10 +22,10 @@
 #include "input/InputStream.hxx"
 #include "util/StringView.hxx"
 
+#include <cassert>
 #include <memory>
 
 #include <stdint.h>
-#include <assert.h>
 #include <string.h>
 
 struct ApeFooter {

src/tag/Builder.cxx

@@ -27,8 +27,8 @@
 
 #include <algorithm>
 #include <array>
+#include <cassert>
 
-#include <assert.h>
 #include <stdlib.h>
 
 TagBuilder::TagBuilder(const Tag &other) noexcept

src/tag/FixString.cxx

@@ -23,7 +23,8 @@
 #include "util/StringView.hxx"
 #include "util/UTF8.hxx"
 
-#include <assert.h>
+#include <cassert>
+
 #include <stdlib.h>
 
 gcc_pure

src/tag/MixRamp.cxx

@@ -23,7 +23,7 @@
 #include "util/ASCII.hxx"
 #include "util/StringView.hxx"
 
-#include <assert.h>
+#include <cassert>
 
 template<typename T>
 static bool

src/tag/ParseName.cxx

@@ -21,7 +21,8 @@
 #include "util/ASCII.hxx"
 #include "util/StringView.hxx"
 
-#include <assert.h>
+#include <cassert>
+
 #include <string.h>
 
 TagType

src/tag/Pool.cxx

@@ -23,9 +23,9 @@
 #include "util/VarSize.hxx"
 #include "util/StringView.hxx"
 
+#include <cassert>
 #include <limits>
 
-#include <assert.h>
 #include <string.h>
 #include <stdlib.h>
 #include <stdint.h>

src/tag/ReplayGain.cxx

@@ -23,7 +23,7 @@
 #include "util/ASCII.hxx"
 #include "util/NumberParser.hxx"
 
-#include <assert.h>
+#include <cassert>
 
 template<typename T>
 static bool

src/tag/Tag.cxx

@@ -21,7 +21,7 @@
 #include "Pool.hxx"
 #include "Builder.hxx"
 
-#include <assert.h>
+#include <cassert>
 
 void
 Tag::Clear() noexcept

src/tag/VorbisComment.cxx

@@ -20,7 +20,7 @@
 #include "VorbisComment.hxx"
 #include "util/StringView.hxx"
 
-#include <assert.h>
+#include <cassert>
 
 StringView
 GetVorbisCommentValue(StringView entry, StringView name) noexcept