p11-kit: fix parallel build failures

p11-kit: fix parallel build failures

It fails occasionally with missing generated header files:

| ../git/common/asn1.c:42:10: fatal error: openssl.asn.h: No such file or directory
|    42 | #include "openssl.asn.h"
|       |          ^~~~~~~~~~~~~~~
| compilation terminated.

According to meson manual page:

https://mesonbuild.com/Wrap-best-practices-and-tips.html#declare-generated-headers-explicitly

'asn_h_dep' should be a dependency of static_library target 'libp11_asn1'
to make sure that required header files generated before compile
common/asn1.c.

Signed-off-by: Kai Kang <kai.kang@windriver.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>