wayland-egl-symbols-check: pass the DSO name via the build system

The location of the file is build system specific so, keep it there.

Cc: Daniel Stone <daniels@collabora.com>
Suggested-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Arnaud Vrac <avrac@freebox.fr>
diff --git a/Makefile.am b/Makefile.am
index 1e934fe..deafc04 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -191,6 +191,7 @@
 	export WAYLAND_SCANNER='$(top_builddir)/wayland-scanner'	\
 	TEST_DATA_DIR='$(top_srcdir)/tests/data'			\
 	TEST_OUTPUT_DIR='$(top_builddir)/tests/output'			\
+	WAYLAND_EGL_LIB='$(top_builddir)/egl/.libs/libwayland-egl.so'	\
 	SED=$(SED)							\
 	;
 
diff --git a/egl/wayland-egl-symbols-check b/egl/wayland-egl-symbols-check
index e7105ea..e107362 100755
--- a/egl/wayland-egl-symbols-check
+++ b/egl/wayland-egl-symbols-check
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-FUNCS=$(nm -D --defined-only ${1-.libs/libwayland-egl.so} | grep -o "T .*" | cut -c 3- | while read func; do
+FUNCS=$(nm -D --defined-only ${WAYLAND_EGL_LIB} | grep -o "T .*" | cut -c 3- | while read func; do
 ( grep -q "^$func$" || echo $func )  <<EOF
 wl_egl_window_resize
 wl_egl_window_create