cbfstool/lzma: Remove C++ remnants

The original lzma code was probably designed as a library, and had
tons of checks for __cplusplus and extern "C". They were not removed
when imported, but remove them now.

Change-Id: I4ae6e7739d191093c57130de8ae40da835e81bd1
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/4835
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

util/cbfstool/lzma/C/LzmaDec.h

@@ -6,10 +6,6 @@
 
 #include "Types.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 /* #define _LZMA_PROB32 */
 /* _LZMA_PROB32 can increase the speed on some CPUs,
    but memory usage for CLzmaDec::probs will be doubled in that case */
@@ -224,8 +220,4 @@ SRes LzmaDecode(uint8_t *dest, size_t *destLen, const uint8_t *src, size_t *srcL
     const uint8_t *propData, unsigned propSize, ELzmaFinishMode finishMode,
     ELzmaStatus *status, ISzAlloc *alloc);
 
-#ifdef __cplusplus
-}
-#endif
-
 #endif