* config/alpha/alpha.md, arm/arm.c, darwin.c, frv/frv.md,
        m32r/m32r.c, m32r/m32r.c, mn10300/mn10300.md, pa/pa.c,
        rs6000/rs6000.c, s390/s390.md, sh/sh.md, sparc/sparc.c:
        Always use set_unique_reg_note to add REG_EQUAL notes.

From-SVN: r120353