tile: export a handful of symbols appropriately

This was shown up by running with "allmodconfig".  I used
EXPORT_SYMBOL() to match existing conventions in files that
were already exporting symbols, or that were exported that way
by other architectures, and otherwise EXPORT_SYMBOL_GPL().

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/arch/tile/lib/exports.c b/arch/tile/lib/exports.c
index dd5f0a3..4385cb6 100644
--- a/arch/tile/lib/exports.c
+++ b/arch/tile/lib/exports.c
@@ -55,6 +55,8 @@
 EXPORT_SYMBOL(hv_dev_close);
 EXPORT_SYMBOL(hv_sysconf);
 EXPORT_SYMBOL(hv_confstr);
+EXPORT_SYMBOL(hv_get_rtc);
+EXPORT_SYMBOL(hv_set_rtc);
 
 /* libgcc.a */
 uint32_t __udivsi3(uint32_t dividend, uint32_t divisor);