bash prompt: return early from __git_ps1() when not in a git repository

... to gain one level of indentation for the bulk of the function.

(The patch looks quite unreadable, you'd better check it with 'git
diff -w'.)

Signed-off-by: SZEDER Gábor <szeder@ira.uka.de>

contrib/completion/git-prompt.sh

@@ -341,7 +341,9 @@ __git_ps1 ()
 			#In PC mode PS1 always needs to be set
 			PS1="$ps1pc_start$ps1pc_end"
 		fi
-	else
+		return
+	fi
+
 	local r=""
 	local b=""
 	local step=""
@@ -457,5 +459,4 @@ __git_ps1 ()
 		# NO color option unless in PROMPT_COMMAND mode
 		printf -- "$printf_format" "$c${b##refs/heads/}${f:+$z$f}$r$p"
 	fi
-	fi
 }