fix issue on big endian architecture

OSMO_IS_LITTLE_ENDIAN is always defined and has a value of
either 0 or 1
as a result in byteswap.h the corresponding swap functions
will be always called, independent of the endianess

Signed-off-by: Thorsten Alteholz <osmocom@alteholz.de>
Change-Id: I4a09d2d8ccf155e70a3977ae1747758b6bc5125e
diff --git a/include/osmocom/core/byteswap.h b/include/osmocom/core/byteswap.h
index 1ea5b3d..cecdc63 100644
--- a/include/osmocom/core/byteswap.h
+++ b/include/osmocom/core/byteswap.h
@@ -32,7 +32,7 @@
 	return out;
 }
 
-#ifdef OSMO_IS_LITTLE_ENDIAN
+#if OSMO_IS_LITTLE_ENDIAN == 1
 #define osmo_ntohl(x)	osmo_swab32(x)
 #define osmo_ntohs(x)	osmo_swab16(x)
 #define osmo_htonl(x)	osmo_swab32(x)