freebsd_network: Define _KERNEL for C++ files too.

This also allows the removal of a function that is also in the cpufunc.h header.

src/libs/compat/freebsd_network/Jamfile

@@ -11,6 +11,7 @@ Includes [ FGristFiles kernel_c++_structs.h ]
 	: <src!system!kernel>kernel_c++_struct_sizes.h ;
 
 SubDirCcFlags [ FDefines _KERNEL=1 ] ;
+SubDirC++Flags [ FDefines _KERNEL=1 ] ;
 
 KernelStaticLibrary libfreebsd_network.a :
 	bus.cpp

src/libs/compat/freebsd_network/bus.cpp

@@ -62,18 +62,6 @@ struct internal_intr {
 static int32 intr_wrapper(void *data);
 
 
-static int
-fls(int mask)
-{
-	int bit;
-	if (mask == 0)
-		return (0);
-	for (bit = 1; mask != 1; bit++)
-		mask = (unsigned int)mask >> 1;
-	return (bit);
-}
-
-
 static area_id
 map_mem(void **virtualAddr, phys_addr_t _phy, size_t size, uint32 protection,
 	const char *name)