Add -fvisibility=default

PKGBUILD

@@ -1,7 +1,7 @@
 # Maintainer: Arthur Sonzogni <sonzogniarthur+ftxui at gmail dot com>
 # Maintainer: Aditya Gupta <adityag.ug19.cs at  nitp.ac.in>
 pkgname=ftxui-git
-pkgver=r413.7c3ca1b
+pkgver=r900.da2491b3
 pkgrel=1
 pkgdesc="FTXUI is a C++ Functional Terminal User Interface library."
 arch=("any")
@@ -29,6 +29,7 @@ build() {
     -DFTXUI_BUILD_TESTS=OFF \
     -DFTXUI_BUILD_DOCS=OFF \
     -DCMAKE_BUILD_TYPE=Release \
+    -DCMAKE_CXX_FLAGS="-fvisibility=default" \
     -DCMAKE_INSTALL_PREFIX=/usr \
     ..