[Gnu-morello] [PATCH 2/2] morello, testsuite: Fix up morello-stubs-static.d

The expected disassembly for this test is testing for the wrong thing: it expects the adrp immediate to be zero-extended instead of sign-extended, which is incorrect. That shows up as a test failure after fixing the disassembly in the previous patch. This patch fixes the test.

Tested on aarch64-none-elf, OK for users/ARM/morello-binutils-gdb-master?

Thanks, Alex