bpf: Remove redundant ifdef

Remove a useless ifdef __NR_bpf as requested by Wang Nan.

Inline one-line static functions as it was in the bpf_sys.h file.
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/r/828ab1ff-4dcf-53ff-c97b-074adb895006@huawei.comAcked-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/lib/bpf/bpf.c

@@ -42,21 +42,15 @@
 # endif
 #endif
 
-static __u64 ptr_to_u64(const void *ptr)
+static inline __u64 ptr_to_u64(const void *ptr)
 {
 	return (__u64) (unsigned long) ptr;
 }
 
-static int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
+static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
 			  unsigned int size)
 {
-#ifdef __NR_bpf
 	return syscall(__NR_bpf, cmd, attr, size);
-#else
-	fprintf(stderr, "No bpf syscall, kernel headers too old?\n");
-	errno = ENOSYS;
-	return -1;
-#endif
 }
 
 int bpf_create_map(enum bpf_map_type map_type, int key_size,