[ELF/AArch64] Fix correct TCB aligment calculation

This patch fixes the TLS local relocations alignment done by @238258.
As pointed out, the TLS size should not be considered, but rather the
TCB size based on maximum output segment alignment.  Although it has
not shown in the TLS simple cases for test-suite, more comprehensible
tests with more local TLS variable showed wrong relocations values
being generated.

The local TLS testcase is expanded to add more tls variable (both
exported and static) initialized or not.

llvm-svn: 238960