crt: msvcr80.def.in: Define X64 pow and powf as DATA

In all other msvcr* versions is X64 pow and powf defined as DATA. Do it
also in msvcr80.def.in.

Signed-off-by: Martin Storsjö <martin@martin.st>

mingw-w64-crt/lib64/msvcr80.def.in

diff --git a/mingw-w64-crt/lib64/msvcr80.def.in b/mingw-w64-crt/lib64/msvcr80.def.in
index 6fa6ef3..db124ed 100644
--- a/mingw-w64-crt/lib64/msvcr80.def.in
+++ b/mingw-w64-crt/lib64/msvcr80.def.in
@@ -842,8 +842,8 @@
 modf
 modff
 perror
-;pow
-;powf
+pow DATA
+powf DATA
 printf
 __ms_printf == printf
 putc