CryptoPkg: Update code to be more C11 compliant by using __func__

__FUNCTION__ is a pre-standard extension that gcc and Visual C++ among
others support, while __func__ was standardized in C99.

Since it's more standard, replace __FUNCTION__ with __func__ throughout
CryptoPkg.

Signed-off-by: Rebecca Cran <rebecca@bsdio.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>

CryptoPkg/Library/TlsLib/TlsProcess.c

@@ -127,7 +127,7 @@ TlsDoHandshake (
       DEBUG ((
         DEBUG_ERROR,
         "%a SSL_HANDSHAKE_ERROR State=0x%x SSL_ERROR_%a\n",
-        __FUNCTION__,
+        __func__,
         SSL_get_state (TlsConn->Ssl),
         Ret == SSL_ERROR_SSL ? "SSL" : Ret == SSL_ERROR_SYSCALL ? "SYSCALL" : "ZERO_RETURN"
         ));
@@ -141,7 +141,7 @@ TlsDoHandshake (
         DEBUG ((
           DEBUG_ERROR,
           "%a ERROR 0x%x=L%x:F%x:R%x\n",
-          __FUNCTION__,
+          __func__,
           ErrorCode,
           ERR_GET_LIB (ErrorCode),
           ERR_GET_FUNC (ErrorCode),