apx-ndd-tls-1[ab].c: Add -std=gnu17

Since GCC 15 defaults to -std=gnu23, add -std=gnu17 to apx-ndd-tls-1[ab].c
to avoid:

gcc.target/i386/apx-ndd-tls-1a.c: In function ‘k’:
gcc.target/i386/apx-ndd-tls-1a.c:29:7: error: too many arguments to function ‘l’
gcc.target/i386/apx-ndd-tls-1a.c:25:5: note: declared here

	* gcc.target/i386/apx-ndd-tls-1a.c: -std=gnu17.
	* gcc.target/i386/apx-ndd-tls-1b.c: Likewise.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>