clang-tidy: simplify bool

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

src/crwimage_int.cpp

@@ -345,11 +345,10 @@ namespace Exiv2::Internal {
         append(blob, reinterpret_cast<const byte*>(signature_), 8);
         o += 8;
         // Pad as needed
-        if (pPadding_.empty() == false) {
+        if (!pPadding_.empty()) {
             assert(padded_ == offset_ - o);
             append(blob, pPadding_.data(), padded_);
-        }
+        } else {
-        else {
             for (uint32_t i = o; i < offset_; ++i) {
                 blob.push_back(0);
                 ++o;

src/pngimage.cpp

@@ -681,22 +681,17 @@ namespace Exiv2 {
             } else if (!strcmp(szChunk, "tEXt") || !strcmp(szChunk, "zTXt") || !strcmp(szChunk, "iTXt") ||
                        !strcmp(szChunk, "iCCP")) {
                 DataBuf key = PngChunk::keyTXTChunk(chunkBuf, true);
-                if (key.empty() == false && (
+                if (!key.empty() &&
-                    compare("Raw profile type exif", key, 21) ||
+                    (compare("Raw profile type exif", key, 21) || compare("Raw profile type APP1", key, 21) ||
-                    compare("Raw profile type APP1", key, 21) ||
+                     compare("Raw profile type iptc", key, 21) || compare("Raw profile type xmp", key, 20) ||
-                    compare("Raw profile type iptc", key, 21) ||
-                    compare("Raw profile type xmp",  key, 20) ||
                      compare("XML:com.adobe.xmp", key, 17) ||
                      compare("icc", key, 3) ||  // see test/data/imagemagick.png
-                    compare("ICC",                   key,  3) ||
+                     compare("ICC", key, 3) || compare("Description", key, 11))) {
-                    compare("Description",           key, 11)))
-                {
 #ifdef EXIV2_DEBUG_MESSAGES
                     std::cout << "Exiv2::PngImage::doWriteMetadata: strip " << szChunk
                               << " chunk (length: " << dataOffset << ")" << std::endl;
 #endif
-                } else
+                } else {
-                {
 #ifdef EXIV2_DEBUG_MESSAGES
                     std::cout << "Exiv2::PngImage::doWriteMetadata: write " << szChunk
                               << " chunk (length: " << dataOffset << ")" << std::endl;