user/Makefile: Fix typo and capitalization in comment section

Signed-off-by: Eugen Cazacu <green182day@hotmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

usr/Makefile

@@ -49,10 +49,10 @@ $(deps_initramfs): ;
 
 $(deps_initramfs): klibcdirs
 # We rebuild initramfs_data.cpio if:
-# 1) Any included file is newer then initramfs_data.cpio
+# 1) Any included file is newer than initramfs_data.cpio
 # 2) There are changes in which files are included (added or deleted)
 # 3) If gen_init_cpio are newer than initramfs_data.cpio
-# 4) arguments to gen_initramfs.sh changes
+# 4) Arguments to gen_initramfs.sh changes
 $(obj)/$(datafile_y): $(obj)/gen_init_cpio $(deps_initramfs) klibcdirs
 	$(Q)$(initramfs) -l $(ramfs-input) > $(obj)/$(datafile_d_y)
 	$(call if_changed,initfs)