lib/zlib_inflate/inffast: Check config in C to avoid unused function …

…warning

Building Linux for ppc64le with Ubuntu clang version 12.0.0-3ubuntu1~21.04.1
shows the warning below.

    arch/powerpc/boot/inffast.c:20:1: warning: unused function 'get_unaligned16' [-Wunused-function]
    get_unaligned16(const unsigned short *p)
    ^
    1 warning generated.

Fix it, by moving the check from the preprocessor to C, so the compiler
sees the use.

Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>

lib/zlib_inflate/inffast.c

@@ -254,11 +254,7 @@ void inflate_fast(z_streamp strm, unsigned start)
 			sfrom = (unsigned short *)(from);
 			loops = len >> 1;
 			do
-#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
-			    *sout++ = *sfrom++;
-#else
-			    *sout++ = get_unaligned16(sfrom++);
-#endif
+			    *sout++ = CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS ? *sfrom++ : get_unaligned16(sfrom++);
 			while (--loops);
 			out = (unsigned char *)sout;
 			from = (unsigned char *)sfrom;