Make release builds work

Since release builds had -Werror on, every warning is counted as an error, and the #pragmas that supressed that warning caused a wrning them selfs.

CMakeLists.txt

@@ -14,7 +14,7 @@ target_link_libraries(aptdec PRIVATE m)
 
 # Throw errors on warnings on release builds
 if(CMAKE_BUILD_TYPE MATCHES "Release")
-    target_compile_options(aptdec PRIVATE -Wall -Wextra -pedantic -Werror)
+    target_compile_options(aptdec PRIVATE -Wall -Wextra -pedantic -Wno-missing-field-initializers -Werror)
 else()
     target_compile_options(aptdec PRIVATE -Wall -Wextra -pedantic)
 endif()

src/pngio.c

@@ -26,9 +26,6 @@
 
 #include "pngio.h"
 
-#pragma GCC diagnostic ignored "-Wmissing-field-initializers"
-#pragma clang diagnostic ignored "-Wmissing-field-initializers"
-
 int mapOverlay(char *filename, rgb_t **crow, int nrow, int zenith, int MCIR) {
 	FILE *fp = fopen(filename, "rb");
 	if(!fp) {