perf genelf: Fix NO_LIBDW=1 build

With NO_LIBDW=1 a new unused-parameter warning/error has appeared:
```
util/genelf.c: In function ‘jit_write_elf’:
util/genelf.c:163:32: error: unused parameter ‘load_addr’ [-Werror=unused-parameter]
163 | jit_write_elf(int fd, uint64_t load_addr, const char *sym,
```

Fixes: e3f612c1d8f3 ("perf genelf: Remove libcrypto dependency and use built-in sha1()")
Signed-off-by: Ian Rogers <[e-mail]>
Tested-by: Namhyung Kim <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Namhyung Kim <[e-mail]>

tools/perf/util/genelf.c

···
  * csize: the code size in bytes
  */
 int
-jit_write_elf(int fd, uint64_t load_addr, const char *sym,
+jit_write_elf(int fd, uint64_t load_addr __maybe_unused, const char *sym,
 	      const void *code, int csize,
 	      void *debug __maybe_unused, int nr_debug_entries __maybe_unused,
 	      void *unwinding, uint64_t unwinding_header_size, uint64_t unwinding_size)