* sparc-tdep.c (sparc_gdbarch_skip_prologue): Kill, duplicates
sparc_skip_prologue.
(sparc_skip_prologue): Kill frameless_p arg, and use line number
information to find prologue when possible.
(sparc_prologue_frameless_p): Call examine_prologue directly.
(sparc_gdbarch_init): Update set_gdbarch_skip_prologue call.
* config/sparc/tm-sparc.h (sparc_skip_prologue): Update for killed
second argument.
(SKIP_PROLOGUE): Likewise.