Revert "crt: Include _strftime_l in msvcrt.def.in"

This reverts commit 16ad1d4e426becb19ece4cfa90f33e7d7cd96e53.

_strftime_l doesn't actually seem to exist in the plain msvcrt.dll,
not even on windows 10.

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

mingw-w64-crt/lib-common/msvcrt.def.in

diff --git a/mingw-w64-crt/lib-common/msvcrt.def.in b/mingw-w64-crt/lib-common/msvcrt.def.in
index 9639e0b..2b9af5c 100644
--- a/mingw-w64-crt/lib-common/msvcrt.def.in
+++ b/mingw-w64-crt/lib-common/msvcrt.def.in
@@ -1481,7 +1481,6 @@
 strerror
 ; strerror_s replaced by emu
 strftime
-_strftime_l
 strlen
 strncat
 strncat_s