MdeModulePkg CapsuleApp: Refine -N option help information
MdeModulePkg CapsuleApp: Refine -N option help information

-N option is used to append a Capsule Header to an existing
FMP capsule image with its ImageTypeId supported by the system.

Cc: Michael D Kinney <fd20bc543a9f65bb633fac7d08a403c1f1c8eb6c@intel.com>
Cc: Jiewen Yao <364a90bfebd1f362ebb7b48e4bf8ec010adef203@intel.com>
Cc: Yonghong Zhu <78d981fe33a016071af5222c56d5cf77f30fb0b2@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <5c6bb72efe464613af94e84c05522a361b23844a@intel.com>
Reviewed-by: Jiewen Yao <364a90bfebd1f362ebb7b48e4bf8ec010adef203@intel.com>

MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2