elf, uapi: Add types ElfXX_Verdef and ElfXX_Veraux

The types are used by tools/testing/selftests/vDSO/parse_vdso.c.

To be able to build the vDSO selftests without a libc dependency,
add the types to the kernels own UAPI headers.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/symversion.html#VERDEFEXTS
Link: https://lore.kernel.org/all/20250226-parse_vdso-nolibc-v2-6-28e14e031ed8@linutronix.de

Author: t-8ch

include/uapi/linux/elf.h

@@ -491,4 +491,34 @@ typedef struct elf64_note {
 /* Bits for GNU_PROPERTY_AARCH64_FEATURE_1_BTI */
 #define GNU_PROPERTY_AARCH64_FEATURE_1_BTI	(1U << 0)
 
+typedef struct {
+  Elf32_Half	vd_version;
+  Elf32_Half	vd_flags;
+  Elf32_Half	vd_ndx;
+  Elf32_Half	vd_cnt;
+  Elf32_Word	vd_hash;
+  Elf32_Word	vd_aux;
+  Elf32_Word	vd_next;
+} Elf32_Verdef;
+
+typedef struct {
+  Elf64_Half	vd_version;
+  Elf64_Half	vd_flags;
+  Elf64_Half	vd_ndx;
+  Elf64_Half	vd_cnt;
+  Elf64_Word	vd_hash;
+  Elf64_Word	vd_aux;
+  Elf64_Word	vd_next;
+} Elf64_Verdef;
+
+typedef struct {
+  Elf32_Word    vda_name;
+  Elf32_Word    vda_next;
+} Elf32_Verdaux;
+
+typedef struct {
+  Elf64_Word    vda_name;
+  Elf64_Word    vda_next;
+} Elf64_Verdaux;
+
 #endif /* _UAPI_LINUX_ELF_H */