Revert "Fix cursor move with wide glyphs"

This reverts commit 7473a8d1a57e5f9aba41b953f4e498c35e1c9dc5.

This patch needs some more work. It caused regressions with programs that use
GNU readline, etc.

Original test-case example from Tim Culverhouse <tim@timculverhouse.com>:

	printf " 😀" && sleep 2 && printf "\e[D" && sleep 2 && printf "\e[D" && sleep 2

After the patch it caused regressions, example test-case:

	printf "A字\bB\n"

1 files changed, 3 insertions, 7 deletions

diff --git a/st.c b/st.c
index 683493d..b9f66e7 100644
--- a/st.c
+++ b/st.c
@@ -86,8 +86,8 @@ enum escape_state {
 
 typedef struct {
         Glyph attr; /* current char attributes */
-        int x; /* terminal column */
-        int y; /* terminal row */
+        int x;
+        int y;
         char state;
 } TCursor;
 
@@ -2175,16 +2175,12 @@ tstrsequence(uchar c)
 void
 tcontrolcode(uchar ascii)
 {
-        size_t i;
-
         switch (ascii) {
         case '\t':   /* HT */
                 tputtab(1);
                 return;
         case '\b':   /* BS */
-                for (i = 1; term.c.x && term.line[term.c.y][term.c.x - i].u == 0; ++i)
-                        ;
-                tmoveto(term.c.x - i, term.c.y);
+                tmoveto(term.c.x-1, term.c.y);
                 return;
         case '\r':   /* CR */
                 tmoveto(0, term.c.y);