Remove not-implemented methods from BufferWriter (#36368)

diff --git a/src/lib/support/BufferWriter.h b/src/lib/support/BufferWriter.h
index 64c22af..ad47425 100644
--- a/src/lib/support/BufferWriter.h
+++ b/src/lib/support/BufferWriter.h
@@ -87,28 +87,8 @@
     uint8_t * Buffer() { return mBuf; }
     const uint8_t * Buffer() const { return mBuf; }
 
-    BufferWriter & Format(const char * format, ...) ENFORCE_FORMAT(2, 3)
-    {
-        va_list args;
-        va_start(args, format);
-        VFormat(format, args);
-        va_end(args);
-        return *this;
-    }
-
     void Reset() { mNeeded = 0; }
 
-    /// Since this uses vsnprintf internally, on overflow
-    /// this will write one less byte that strictly can be
-    /// written (since null terminator will be in the binary data)
-    BufferWriter & VFormat(const char * format, va_list args) ENFORCE_FORMAT(2, 0);
-
-    /// Assume a specific size for the buffer instead of mSize
-    ///
-    /// This is to allow avoiding off-by-one overflow truncation
-    /// when we know the underlying buffer size is larger.
-    BufferWriter & VFormatWithSize(size_t size, const char * format, va_list args) ENFORCE_FORMAT(3, 0);
-
 protected:
     uint8_t * mBuf;
     size_t mSize;