microblaze: Export xmb_manager functions

When TMR_MANAGER is enabled as module there is a need to export functions
which are present in architecture code.

It has been found by running:
make W=1 C=1 allmodconfig
sed -i -e 's/WERROR=y/WERROR=n/g' .config
make C=1 W=1

which errors out like this:
ERROR: modpost: "xmb_manager_register" [drivers/misc/xilinx_tmr_manager.ko] undefined!
ERROR: modpost: "xmb_inject_err" [drivers/misc/xilinx_tmr_inject.ko] undefined!

Fixes: a5e3aaa ("microblaze: Add xmb_manager_register function")
Reported-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/e322dbbbde0feef83f44304ea13249d365d1dc5f.1718799090.git.michal.simek@amd.com

Author: michalsimek

arch/microblaze/kernel/microblaze_ksyms.c

@@ -16,6 +16,7 @@
 #include <asm/page.h>
 #include <linux/ftrace.h>
 #include <linux/uaccess.h>
+#include <asm/xilinx_mb_manager.h>
 
 #ifdef CONFIG_FUNCTION_TRACER
 extern void _mcount(void);
@@ -46,3 +47,12 @@ extern void __udivsi3(void);
 EXPORT_SYMBOL(__udivsi3);
 extern void __umodsi3(void);
 EXPORT_SYMBOL(__umodsi3);
+
+#ifdef CONFIG_MB_MANAGER
+extern void xmb_manager_register(uintptr_t phys_baseaddr, u32 cr_val,
+				 void (*callback)(void *data),
+				 void *priv, void (*reset_callback)(void *data));
+EXPORT_SYMBOL(xmb_manager_register);
+extern asmlinkage void xmb_inject_err(void);
+EXPORT_SYMBOL(xmb_inject_err);
+#endif