lib/pass/: Remove malloc(3)-based APIs, as they're unused

In the last commit, we replaced all of these calls by alloca(3)-based
variants.

Signed-off-by: Alejandro Colomar <[email protected]>

Author: alejandro-colomar

lib/Makefile.am

@@ -136,11 +136,7 @@ libshadow_la_SOURCES = \
 	pam_defs.h \
 	pam_pass.c \
 	pam_pass_non_interactive.c \
-	pass/agetpass.c \
-	pass/agetpass.h \
 	pass/limits.h \
-	pass/areadpass.c \
-	pass/areadpass.h \
 	pass/getpass2.c \
 	pass/getpass2.h \
 	pass/passalloca.c \