gb: Make suspend_ref a plain uint8_t instead of a uint8_t*

The OpenSUSE build is not happy about the uint8_t to uint8_t*
assignment. As the suspend_ref is a mandatory field we can make
it a plain uint8_t. Increase the LIBVERSION as the ABI has changed.
diff --git a/src/gb/Makefile.am b/src/gb/Makefile.am
index f6c69e0..9d1b786 100644
--- a/src/gb/Makefile.am
+++ b/src/gb/Makefile.am
@@ -1,6 +1,6 @@
 # This is _NOT_ the library release version, it's an API version.
 # Please read Chapter 6 "Library interface versions" of the libtool documentation before making any modification
-LIBVERSION=1:0:0
+LIBVERSION=2:0:0
 
 INCLUDES = $(all_includes) -I$(top_srcdir)/include
 AM_CFLAGS = -Wall ${GCC_FVISIBILITY_HIDDEN}