Resolve -Wimplicit-int-conversion warnings

Panel.c:414:49: error: implicit conversion loses integer precision: 'int' to 'short' [-Werror,-Wimplicit-int-conversion]
      this->scrollH = MAXIMUM(this->selectedLen - this->w, 0);
                    ~         ~~~~~~~~~~~~~~~~~~^~~~~~~~~
./Macros.h:11:54: note: expanded from macro 'MAXIMUM'
#define MAXIMUM(a, b)                  ((a) > (b) ? (a) : (b))
                                                     ^

IncSet.c:159:38: error: implicit conversion loses integer precision: 'int' to 'char' [-Werror,-Wimplicit-int-conversion]
         mode->buffer[mode->index] = ch;
                                   ~ ^~

Panel.c:456:24: error: implicit conversion loses integer precision: 'int' to 'char' [-Werror,-Wimplicit-int-conversion]
         buffer[len] = ch;
                     ~ ^~
Panel.c:473:22: error: implicit conversion loses integer precision: 'int' to 'char' [-Werror,-Wimplicit-int-conversion]
         buffer[0] = ch;
                   ~ ^~

1 files changed, 1 insertions, 1 deletions

diff --git a/Panel.h b/Panel.h
index cf110c90..9bb4c77e 100644
--- a/Panel.h
+++ b/Panel.h
@@ -67,7 +67,7 @@ struct Panel_ {
    int selectedLen;
    void* eventHandlerState;
    int scrollV;
-   short scrollH;
+   int scrollH;
    bool needsRedraw;
    bool wasFocus;
    FunctionBar* currentBar;