[PATCH] drm/xe: replace basename() with portable strrchr()

[Carlos Llamas <cmllamas@google.com>]

Commit b0a2ee5567ab ("drm/xe: prepare xe_gen_wa_oob to be multi-use")
introduced a call to basename(). The GNU version of this function is not
portable and fails to build with alternative libc implementations like
musl or bionic. This causes the following build error:

  drivers/gpu/drm/xe/xe_gen_wa_oob.c:130:12: error: assignment to ‘const char *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
    130 |         fn = basename(fn);
        |            ^

While a POSIX version of basename() could be used, it would require a
separate header plus the behavior differs from GNU version in that it
might modify its argument. Not great.

Instead replace basename() with a strrchr() based implementation which
provides the same functionality and avoid portability issues.

Fixes: b0a2ee5567ab ("drm/xe: prepare xe_gen_wa_oob to be multi-use")
Signed-off-by: Carlos Llamas <cmllamas@google.com>
---
 drivers/gpu/drm/xe/xe_gen_wa_oob.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_gen_wa_oob.c b/drivers/gpu/drm/xe/xe_gen_wa_oob.c
index 6581cb0f0e59..0a94a045bcea 100644
--- a/drivers/gpu/drm/xe/xe_gen_wa_oob.c
+++ b/drivers/gpu/drm/xe/xe_gen_wa_oob.c
@@ -125,9 +125,11 @@ static int parse(FILE *input, FILE *csource, FILE *cheader, char *prefix)
 
 static int fn_to_prefix(const char *fn, char *prefix, size_t size)
 {
+	const char *base;
 	size_t len;
 
-	fn = basename(fn);
+	base = strrchr(fn, '/');
+	fn = base ? base + 1 : fn;
 	len = strlen(fn);
 
 	if (len > size - 1)
-- 
2.51.0.rc1.193.gad69d77794-goog