libcamera: MappedFrameBuffer: Use typed Flags<MapModes>

Remove the need for callers to reference PROT_READ/PROT_WRITE directly
from <sys/mman.h> by instead exposing the Read/Write mapping options as
flags from the MappedFrameBuffer class itself.

While here, introduce the <stdint.h> header which is required for the
uint8_t as part of the Plane.

Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/android/jpeg/encoder_libjpeg.cpp

@@ -12,7 +12,6 @@
 #include <iostream>
 #include <sstream>
 #include <string.h>
-#include <sys/mman.h>
 #include <unistd.h>
 #include <vector>
 
@@ -182,7 +181,7 @@ void EncoderLibJpeg::compressNV(Span<const uint8_t> frame)
 int EncoderLibJpeg::encode(const FrameBuffer &source, Span<uint8_t> dest,
 			   Span<const uint8_t> exifData, unsigned int quality)
 {
-	MappedFrameBuffer frame(&source, PROT_READ);
+	MappedFrameBuffer frame(&source, MappedFrameBuffer::MapFlag::Read);
 	if (!frame.isValid()) {
 		LOG(JPEG, Error) << "Failed to map FrameBuffer : "
 				 << strerror(frame.error());

src/android/jpeg/thumbnailer.cpp

@@ -41,7 +41,7 @@ void Thumbnailer::createThumbnail(const FrameBuffer &source,
 				  const Size &targetSize,
 				  std::vector<unsigned char> *destination)
 {
-	MappedFrameBuffer frame(&source, PROT_READ);
+	MappedFrameBuffer frame(&source, MappedFrameBuffer::MapFlag::Read);
 	if (!frame.isValid()) {
 		LOG(Thumbnailer, Error)
 			<< "Failed to map FrameBuffer : "