Update st to version 0.9 (2022-10-25)

st.h

@@ -91,7 +91,7 @@ void tnew(int, int);
 void tresize(int, int);
 void tsetdirtattr(int);
 void ttyhangup(void);
-int ttynew(char *, char *, char *, char **);
+int ttynew(const char *, char *, const char *, char **);
 size_t ttyread(void);
 void ttyresize(int, int);
 void ttywrite(const char *, size_t, int);
@@ -109,7 +109,7 @@ size_t utf8encode(Rune, char *);
 
 void *xmalloc(size_t);
 void *xrealloc(void *, size_t);
-char *xstrdup(char *);
+char *xstrdup(const char *);
 
 /* config.h globals */
 extern char *utmp;
@@ -123,4 +123,4 @@ extern char *termname;
 extern unsigned int tabspaces;
 extern unsigned int defaultfg;
 extern unsigned int defaultbg;
-extern float alpha;
+extern unsigned int defaultcs;