The Thumb2 conditional branch B<cond>.W has a different encoding (T3)
to the unconditional branch B.W (T4) as it needs to record <cond>.
As the encoding is different the B<cond>.W is given a different
relocation type.
ELF for the ARM Architecture 4.6.1.6 (Table-13) states that
R_ARM_THM_JUMP19 should be used for B<cond>.W. At present the
MC layer is using the R_ARM_THM_JUMP24 from B.W.
This change makes B<cond>.W use R_ARM_THM_JUMP19 and alters the
existing test that checks for R_ARM_THM_JUMP24 to expect
R_ARM_THM_JUMP19.
llvm-svn: 271997
353a2286e2