MFC 340466,340473: Move the TLS key map into the adapter softc.

340466:
Move the TLS key map into the adapter softc so non-TOE code can use it.

340473:
Restore the <sys/vmem.h> header to fix build of cxgbe(4) TOM.

vmem's are not just used for TLS memory in TOM and the #include actually
predates the TLS code so should not have been removed when the TLS vmem
moved in r340466.