MFH: r458127

graphics/libraw: unbreak build with Clang 6 (C++14 by default)

In file included from src/libraw_cxx.cpp:5472:
src/../internal/libraw_x3f.cpp:1404:19: error: non-constant-expression cannot be narrowed from type

    'int' to 'int16_t' (aka 'short') in initializer list [-Wc++11-narrowing]
int16_t c[3] = {offset,offset,offset};
                ^~~~~~

src/../internal/libraw_x3f.cpp:1404:19: note: insert an explicit cast to silence this issue

int16_t c[3] = {offset,offset,offset};
                ^~~~~~
                static_cast<int16_t>( )

src/../internal/libraw_x3f.cpp:1404:26: error: non-constant-expression cannot be narrowed from type

    'int' to 'int16_t' (aka 'short') in initializer list [-Wc++11-narrowing]
int16_t c[3] = {offset,offset,offset};
                       ^~~~~~

src/../internal/libraw_x3f.cpp:1404:26: note: insert an explicit cast to silence this issue

int16_t c[3] = {offset,offset,offset};
                       ^~~~~~
                       static_cast<int16_t>( )

src/../internal/libraw_x3f.cpp:1404:33: error: non-constant-expression cannot be narrowed from type

    'int' to 'int16_t' (aka 'short') in initializer list [-Wc++11-narrowing]
int16_t c[3] = {offset,offset,offset};
                              ^~~~~~

src/../internal/libraw_x3f.cpp:1404:33: note: insert an explicit cast to silence this issue

int16_t c[3] = {offset,offset,offset};
                              ^~~~~~
                              static_cast<int16_t>( )

Reported by: antoine (via bug 224669)
Obtained from: upstream
Approved by: ports-secteam blanket