* tm-altosgas.h, tm-i386v-g.h: Remove ancient coff encap configs.

* config/{altosgas.mt, i386v-g.mt, i386v32-g.mt}:  Ditto.
* config/{i386sco.mt,i386v32.mt}:  Remove; identical to i386v.mt.
* config/{go32.mt,i960.mt}:  Remove; they only printed error msgs.
* config/nindy960.mt:  Remove useless MT_CFLAGS setting.
* config/i386aout.mt:  Use tm-i386v.h, not tm-i386v-g.h.

gdb/config/i386aout.mt

@@ -1,4 +1,4 @@
 # Target: Intel 386 with a.out
  
 TDEPFILES= exec.o i386-tdep.o i386-pinsn.o
-TM_FILE= tm-i386v-g.h
+TM_FILE= tm-i386v.h

gdb/config/nindy960.mt

@@ -1,4 +1,3 @@
 # Target: Intel 80960, in an embedded system under the NINDY monitor
 TDEPFILES= exec.o i960-pinsn.o i960-tdep.o nindy-tdep.o remote-nindy.o nindy.o Onindy.o ttybreak.o ttyflush.o
 TM_FILE= tm-nindy960.h
-MT_CFLAGS=