Revert part of "Fix Linux build." to fix swiftshader_unittests

The cl "Fix Linux build." broke swiftshader_unittests on Linux and
MacOS. Reverting part of that cl to fix swiftshader_unittests, and
hopefully keep the part of the cl that fixed the build originally.

Change-Id: I3126a12f12ca7337f18c758db16dd3542dcfc226
Reviewed-on: https://swiftshader-review.googlesource.com/18848
Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>

src/OpenGL/libEGL/main.cpp

diff --git a/src/OpenGL/libEGL/main.cpp b/src/OpenGL/libEGL/main.cpp
index 386c3ea..c850610 100644
--- a/src/OpenGL/libEGL/main.cpp
+++ b/src/OpenGL/libEGL/main.cpp
@@ -643,7 +643,7 @@
 	this->clientGetCurrentContext = egl::getCurrentContext;
 }
 
-extern "C" LibEGLexports *libEGL_swiftshader()
+extern "C" EGLAPI LibEGLexports *libEGL_swiftshader()
 {
 	static LibEGLexports libEGL;
 	return &libEGL;

src/OpenGL/libGLESv2/entry_points.cpp

diff --git a/src/OpenGL/libGLESv2/entry_points.cpp b/src/OpenGL/libGLESv2/entry_points.cpp
index 05afd49..378f9fe 100644
--- a/src/OpenGL/libGLESv2/entry_points.cpp
+++ b/src/OpenGL/libGLESv2/entry_points.cpp
@@ -1420,7 +1420,7 @@
 	this->createFrameBuffer = ::createFrameBuffer;
 }
 
-extern "C" LibGLESv2exports *libGLESv2_swiftshader()
+extern "C" GL_APICALL LibGLESv2exports *libGLESv2_swiftshader()
 {
 	static LibGLESv2exports libGLESv2;
 	return &libGLESv2;